Jashin J. Wu, MD

To the Editor:

Brodalumab, a monoclonal antibody targeting IL-17RA, was approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of moderate to severe chronic plaque psoriasis. The drug is the only biologic agent available for the treatment of psoriasis for which a psoriasis area severity index score of 100 is a primary end point.^1,2 Brodalumab is associated with an FDA boxed warning due to an increased risk for suicidal ideation and behavior (SIB), including completed suicides, during clinical trials.

We sought to characterize national utilization of this effective yet underutilized drug among Medicare beneficiaries by surveying the Medicare Part D Prescriber dataset.³ We tabulated brodalumab utilization statistics and characteristics of high-volume prescribers who had 11 or more annual claims for brodalumab.

Despite its associated boxed warning, the number of Medicare D claims for brodalumab increased by 1756 from 2017 to 2019, surpassing $7 million in costs by 2019. The number of beneficiaries also increased from 11 to 292—a 415.2% annual increase in beneficiaries for whom brodalumab was prescribed (Table 1).

In addition, states in the West and South had the highest utilization rates of brodalumab in 2019. There also was an increasing trend toward high-volume prescribers of brodalumab, with private practice clinicians constituting the majority (Table 2).

There was a substantial increase in advanced practice providers including nurse practitioners and physician assistants who were brodalumab prescribers. Although this trend might promote greater access to brodalumab, it is vital to ensure that advanced practice providers receive targeted training to properly understand the complexities of treatment with brodalumab.

Although the utilization of brodalumab has increased since 2017 (P<.001), it is still underutilized compared to the other IL-17 inhibitors secukinumab and ixekizumab. Secukinumab was FDA approved for the treatment of moderate to severe plaque psoriasis in 2015, followed by ixekizumab in 2016.⁴

According to the Medicare Part D database, both secukinumab and ixekizumab had a higher number of total claims and prescribers compared to brodalumab in the years of their debut.³ In 2015, there were 3593 claims for and 862 prescribers of secukinumab; in 2016, there were 1731 claims for and 681 prescribers of ixekizumab. In contrast, there were only 29 claims for and 11 prescribers of brodalumab in 2017, the year that the drug was approved by the FDA. During the same 3-year period, secukinumab and ixekizumab had a substantially greater number of claims—totals of 176,823 and 55,289, respectively—than brodalumab. The higher number of claims for secukinumab and ixekizumab compared to brodalumab may reflect clinicians’ increasing confidence in prescribing those drugs, given their long-term safety and efficacy. In addition, secukinumab and ixekizumab do not require completion of a Risk Evaluation and Mitigation Strategy (REMS) program, which makes them more readily prescribable.³

Overall, most experts agree that there is no increase in the risk for suicide associated with brodalumab compared to the general population. A 2-year pharmacovigilance report on brodalumab supports the safety of this drug.⁵ All participants who completed suicide during the clinical trials harbored an underlying psychiatric disorder or stressor(s).⁶

Although causation between brodalumab and SIB has not been demonstrated, it remains imperative that prescribers diligently assess patients’ risk of SIB and subsequently their access to appropriate psychiatric services as a precaution, if necessary. This is particularly important for private practice prescribers, who constitute the majority of Medicare D brodalumab claims, because they must ensure collaboration with a multidisciplinary team involving mental health providers. Lastly, considering that the highest number of brodalumab Medicare D claims were in western and southern states, it is critical to note that those 2 regions also harbor comparatively fewer mental health facilities that accept Medicare than other regions of the country.⁷ Prescribers in western and southern states must be mindful of mental health coverage limitations when treating psoriasis patients with brodalumab.

The increase in the number of claims, beneficiaries, and prescribers of brodalumab during its first 3 years of availability might be attributed to its efficacy and safety. On the other hand, the boxed warning and REMS associated with brodalumab might have led to underutilization of this drug compared to other IL-17 inhibitors.

Our analysis is limited by its representative restriction to Medicare patients. There also are limited data on brodalumab given its novelty. Individual attributes of prescribers with fewer than 11 annual claims for brodalumab could not be obtained because of dataset regulations; however, aggregated utilization statistics provide an indication of brodalumab prescribing patterns among all providers. Furthermore, during this analysis, data on the Medicare D database were limited to 2013 through 2020. Studies are needed to determine prescribing patterns of brodalumab since this study period.

To the Editor:

Brodalumab, a monoclonal antibody targeting IL-17RA, was approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of moderate to severe chronic plaque psoriasis. The drug is the only biologic agent available for the treatment of psoriasis for which a psoriasis area severity index score of 100 is a primary end point.^1,2 Brodalumab is associated with an FDA boxed warning due to an increased risk for suicidal ideation and behavior (SIB), including completed suicides, during clinical trials.

We sought to characterize national utilization of this effective yet underutilized drug among Medicare beneficiaries by surveying the Medicare Part D Prescriber dataset.³ We tabulated brodalumab utilization statistics and characteristics of high-volume prescribers who had 11 or more annual claims for brodalumab.

Despite its associated boxed warning, the number of Medicare D claims for brodalumab increased by 1756 from 2017 to 2019, surpassing $7 million in costs by 2019. The number of beneficiaries also increased from 11 to 292—a 415.2% annual increase in beneficiaries for whom brodalumab was prescribed (Table 1).

In addition, states in the West and South had the highest utilization rates of brodalumab in 2019. There also was an increasing trend toward high-volume prescribers of brodalumab, with private practice clinicians constituting the majority (Table 2).

There was a substantial increase in advanced practice providers including nurse practitioners and physician assistants who were brodalumab prescribers. Although this trend might promote greater access to brodalumab, it is vital to ensure that advanced practice providers receive targeted training to properly understand the complexities of treatment with brodalumab.

Although the utilization of brodalumab has increased since 2017 (P<.001), it is still underutilized compared to the other IL-17 inhibitors secukinumab and ixekizumab. Secukinumab was FDA approved for the treatment of moderate to severe plaque psoriasis in 2015, followed by ixekizumab in 2016.⁴

According to the Medicare Part D database, both secukinumab and ixekizumab had a higher number of total claims and prescribers compared to brodalumab in the years of their debut.³ In 2015, there were 3593 claims for and 862 prescribers of secukinumab; in 2016, there were 1731 claims for and 681 prescribers of ixekizumab. In contrast, there were only 29 claims for and 11 prescribers of brodalumab in 2017, the year that the drug was approved by the FDA. During the same 3-year period, secukinumab and ixekizumab had a substantially greater number of claims—totals of 176,823 and 55,289, respectively—than brodalumab. The higher number of claims for secukinumab and ixekizumab compared to brodalumab may reflect clinicians’ increasing confidence in prescribing those drugs, given their long-term safety and efficacy. In addition, secukinumab and ixekizumab do not require completion of a Risk Evaluation and Mitigation Strategy (REMS) program, which makes them more readily prescribable.³

Overall, most experts agree that there is no increase in the risk for suicide associated with brodalumab compared to the general population. A 2-year pharmacovigilance report on brodalumab supports the safety of this drug.⁵ All participants who completed suicide during the clinical trials harbored an underlying psychiatric disorder or stressor(s).⁶

Although causation between brodalumab and SIB has not been demonstrated, it remains imperative that prescribers diligently assess patients’ risk of SIB and subsequently their access to appropriate psychiatric services as a precaution, if necessary. This is particularly important for private practice prescribers, who constitute the majority of Medicare D brodalumab claims, because they must ensure collaboration with a multidisciplinary team involving mental health providers. Lastly, considering that the highest number of brodalumab Medicare D claims were in western and southern states, it is critical to note that those 2 regions also harbor comparatively fewer mental health facilities that accept Medicare than other regions of the country.⁷ Prescribers in western and southern states must be mindful of mental health coverage limitations when treating psoriasis patients with brodalumab.

The increase in the number of claims, beneficiaries, and prescribers of brodalumab during its first 3 years of availability might be attributed to its efficacy and safety. On the other hand, the boxed warning and REMS associated with brodalumab might have led to underutilization of this drug compared to other IL-17 inhibitors.

Our analysis is limited by its representative restriction to Medicare patients. There also are limited data on brodalumab given its novelty. Individual attributes of prescribers with fewer than 11 annual claims for brodalumab could not be obtained because of dataset regulations; however, aggregated utilization statistics provide an indication of brodalumab prescribing patterns among all providers. Furthermore, during this analysis, data on the Medicare D database were limited to 2013 through 2020. Studies are needed to determine prescribing patterns of brodalumab since this study period.

To the Editor:

Brodalumab, a monoclonal antibody targeting IL-17RA, was approved by the US Food and Drug Administration (FDA) in 2017 for the treatment of moderate to severe chronic plaque psoriasis. The drug is the only biologic agent available for the treatment of psoriasis for which a psoriasis area severity index score of 100 is a primary end point.^1,2 Brodalumab is associated with an FDA boxed warning due to an increased risk for suicidal ideation and behavior (SIB), including completed suicides, during clinical trials.

We sought to characterize national utilization of this effective yet underutilized drug among Medicare beneficiaries by surveying the Medicare Part D Prescriber dataset.³ We tabulated brodalumab utilization statistics and characteristics of high-volume prescribers who had 11 or more annual claims for brodalumab.

Despite its associated boxed warning, the number of Medicare D claims for brodalumab increased by 1756 from 2017 to 2019, surpassing $7 million in costs by 2019. The number of beneficiaries also increased from 11 to 292—a 415.2% annual increase in beneficiaries for whom brodalumab was prescribed (Table 1).

In addition, states in the West and South had the highest utilization rates of brodalumab in 2019. There also was an increasing trend toward high-volume prescribers of brodalumab, with private practice clinicians constituting the majority (Table 2).

There was a substantial increase in advanced practice providers including nurse practitioners and physician assistants who were brodalumab prescribers. Although this trend might promote greater access to brodalumab, it is vital to ensure that advanced practice providers receive targeted training to properly understand the complexities of treatment with brodalumab.

Although the utilization of brodalumab has increased since 2017 (P<.001), it is still underutilized compared to the other IL-17 inhibitors secukinumab and ixekizumab. Secukinumab was FDA approved for the treatment of moderate to severe plaque psoriasis in 2015, followed by ixekizumab in 2016.⁴

According to the Medicare Part D database, both secukinumab and ixekizumab had a higher number of total claims and prescribers compared to brodalumab in the years of their debut.³ In 2015, there were 3593 claims for and 862 prescribers of secukinumab; in 2016, there were 1731 claims for and 681 prescribers of ixekizumab. In contrast, there were only 29 claims for and 11 prescribers of brodalumab in 2017, the year that the drug was approved by the FDA. During the same 3-year period, secukinumab and ixekizumab had a substantially greater number of claims—totals of 176,823 and 55,289, respectively—than brodalumab. The higher number of claims for secukinumab and ixekizumab compared to brodalumab may reflect clinicians’ increasing confidence in prescribing those drugs, given their long-term safety and efficacy. In addition, secukinumab and ixekizumab do not require completion of a Risk Evaluation and Mitigation Strategy (REMS) program, which makes them more readily prescribable.³

Overall, most experts agree that there is no increase in the risk for suicide associated with brodalumab compared to the general population. A 2-year pharmacovigilance report on brodalumab supports the safety of this drug.⁵ All participants who completed suicide during the clinical trials harbored an underlying psychiatric disorder or stressor(s).⁶

Although causation between brodalumab and SIB has not been demonstrated, it remains imperative that prescribers diligently assess patients’ risk of SIB and subsequently their access to appropriate psychiatric services as a precaution, if necessary. This is particularly important for private practice prescribers, who constitute the majority of Medicare D brodalumab claims, because they must ensure collaboration with a multidisciplinary team involving mental health providers. Lastly, considering that the highest number of brodalumab Medicare D claims were in western and southern states, it is critical to note that those 2 regions also harbor comparatively fewer mental health facilities that accept Medicare than other regions of the country.⁷ Prescribers in western and southern states must be mindful of mental health coverage limitations when treating psoriasis patients with brodalumab.

The increase in the number of claims, beneficiaries, and prescribers of brodalumab during its first 3 years of availability might be attributed to its efficacy and safety. On the other hand, the boxed warning and REMS associated with brodalumab might have led to underutilization of this drug compared to other IL-17 inhibitors.

Our analysis is limited by its representative restriction to Medicare patients. There also are limited data on brodalumab given its novelty. Individual attributes of prescribers with fewer than 11 annual claims for brodalumab could not be obtained because of dataset regulations; however, aggregated utilization statistics provide an indication of brodalumab prescribing patterns among all providers. Furthermore, during this analysis, data on the Medicare D database were limited to 2013 through 2020. Studies are needed to determine prescribing patterns of brodalumab since this study period.

Acute generalized pustular psoriasis (GPP) is a rare severe variant of psoriasis characterized by the sudden widespread eruption of sterile pustules.^1,2 The cutaneous manifestations of GPP also may be accompanied by signs of systemic inflammation, including fever, malaise, and leukocytosis.² Complications are common and may be life-threatening, especially in older patients with comorbid diseases.³ Generalized pustular psoriasis most commonly occurs in patients with a preceding history of psoriasis, but it also may occur de novo.⁴ Generalized pustular psoriasis is associated with notable morbidity and mortality, and relapses are common.^3,4 Many triggers of GPP have been identified, including initiation and withdrawal of various medications, infections, pregnancy, and other conditions.^5,6 Although GPP most often occurs in adults, it also may arise in children and infants.³ In pregnancy, GPP is referred to as impetigo herpetiformis, despite having no etiologic ties with either herpes simplex virus or staphylococcal or streptococcal infection. Impetigo herpetiformis is considered one of the most dangerous dermatoses of pregnancy because of high rates of associated maternal and fetal morbidity.^6,7

Acute GPP has proven to be a challenging disease to treat due to the rarity and relapsing-remitting nature of the disease; additionally, there are relatively few randomized controlled trials investigating the efficacy and safety of treatments for GPP. This review summarizes the features of GPP, including the pathophysiology of the disease, clinical and histological manifestations, and recommendations for management based on a PubMed search of articles indexed for MEDLINE using MeSH terms pertaining to the disease, including generalized pustular psoriasis, impetigo herpetiformis, and von Zumbusch psoriasis.

Pathophysiology

The pathophysiology of GPP is only partially understood, but it is thought to have a distinct pattern of immune activation compared with plaque psoriasis.⁸ Although there is a considerable amount of overlap and cross-talk among cytokine pathways, GPP generally is driven by innate immunity and unrestrained IL-36 cytokine activity. In contrast, adaptive immune responses—namely the tumor necrosis factor (TNF) α, IL-23, IL-17, and IL-22 axes—underlie plaque psoriasis.^8-10

Proinflammatory IL-36 cytokines α, β, and γ, which are all part of the IL-1 superfamily, bind to the IL-36 receptor (IL-36R) to recruit and activate immune cells via various mediators, including IL-1β; IL-8; and chemokines CXCL1, CXCL2, and CXCL8.³ The IL-36 receptor antagonist (IL-36ra) acts to inhibit this inflammatory cascade.^3,8 Microarray analyses of skin biopsy samples have shown that overexpression of IL-17A, TNF-α, IL-1, and IL-36 are seen in both GPP and plaque psoriasis lesions, but GPP lesions had higher expression of IL-1β, IL-36α, and IL-36γ and elevated neutrophil chemokines—CXCL1, CXCL2, and CXCL8—compared with plaque psoriasis lesions.⁸

Gene Mutations Associated With GPP

There are 3 gene mutations that have been associated with pustular variants of psoriasis, though these mutations account for a minority of cases of GPP.⁴ Genetic screenings are not routinely indicated in patients with GPP, but they may be warranted in severe cases when a familial pattern of inheritance is suspected.⁴

IL36RN—The gene IL36RN codes the anti-inflammatory IL-36ra. Loss-of-function mutations in IL36RN lead to impairment of IL-36ra and consequently hyperactivity of the proinflammatory responses triggered by IL-36.³ Homozygous and heterozygous mutations in IL36RN have been observed in both familial and sporadic cases of GPP.^11-13 Subsequent retrospective analyses have identified the presence of IL36RN mutations in patients with GPP with frequencies ranging from 23% to 37%.^14-17IL36RN mutations are thought to be more common in patients without concomitant plaque psoriasis and have been associated with severe disease and early disease onset.¹⁵

CARD14—A gain-of-function mutation in CARD14 results in overactivation of the proinflammatory nuclear factor κB pathway and has been implicated in cases of GPP with concurrent psoriasis vulgaris. Interestingly, this may suggest distinct etiologies underlying GPP de novo and GPP in patients with a history of psoriasis.^18,19

AP1S3—A loss-of-function mutation in AP1S3 results in abnormal endosomal trafficking and autophagy as well as increased expression of IL-36α.^20,21

Clinical Presentation and DiagnosisCutaneous Manifestations of GPP

Generalized pustular psoriasis is characterized by the onset of widespread 2- to 3-mm sterile pustules on erythematous skin or within psoriasiform plaques⁴ (Figure). In patients with skin of color, the erythema may appear less obvious or perhaps slightly violaceous compared to White skin. Pustules may coalesce to form “lakes” of pus.⁵ Cutaneous symptoms include pain, burning, and pruritus. Associated mucosal findings may include cheilitis, geographic tongue, conjunctivitis, and uveitis.⁴

The severity of symptoms can vary greatly among patients as well as between flares within the same patient.^2,3 Four distinct patterns of GPP have been described. The von Zumbusch pattern is characterized by a rapid, generalized, painful, erythematous and pustular eruption accompanied by fever and asthenia. The pustules usually resolve after several days with extensive scaling. The annular pattern is characterized by annular, erythematous, scaly lesions with pustules present centrifugally. The lesions enlarge by centrifugal expansion over a period of hours to days, while healing occurs centrally. The exanthematic type is an acute eruption of small pustules that abruptly appear and disappear within a few days, usually from infection or medication initiation. Sometimes pustules appear within or at the edge of existing psoriatic plaques in a localized pattern—the fourth pattern—often following the exposure to irritants (eg, tars, anthralin).⁵

Impetigo Herpetiformis—Impetigo herpetiformis is a form of GPP associated with pregnancy. It generally presents early in the third trimester with symmetric erythematous plaques in flexural and intertriginous areas with pustules present at lesion margins. Lesions expand centrifugally, with pustulation present at the advancing edge.^6,7 Patients often are acutely ill with fever, delirium, vomiting, and tetany. Mucous membranes, including the tongue, mouth, and esophagus, also may be involved. The eruption typically resolves after delivery, though it often recurs with subsequent pregnancies, with the morbidity risk rising with each successive pregnancy.⁷

Systemic and Extracutaneous Manifestations of GPP

Although the severity of GPP is highly variable, skin manifestations often are accompanied by systemic manifestations of inflammation, including fever and malaise. Common laboratory abnormalities include leukocytosis with peripheral neutrophilia, a high serum C-reactive protein level, hypocalcemia, and hypoalbuminemia.²² Abnormal liver enzymes often are present and result from neutrophilic cholangitis, with alternating strictures and dilations of biliary ducts observed on magnetic resonance imaging.²³ Additional laboratory abnormalities are provided in Table 2. Other extracutaneous findings associated with GPP include arthralgia, edema, and characteristic psoriatic nail changes.⁴ Fatal complications include acute respiratory distress syndrome, renal dysfunction, cardiovascular shock, and sepsis.^24,25

Histologic Features

Given the potential for the skin manifestations of GPP to mimic other disorders, a skin biopsy is warranted to confirm the diagnosis. Generalized pustular psoriasis is histologically characterized by the presence of subcorneal macropustules (ie, spongiform pustules of Kogoj) formed by neutrophil infiltration into the spongelike network of the epidermis.⁶ Otherwise, the architecture of the epithelium in GPP is similar to that seen with plaque psoriasis, with parakeratosis, acanthosis, rete-ridge elongation, diminished stratum granulosum, and thinning of the suprapapillary epidermis, though the inflammatory cell infiltrate and edema are markedly more severe in GPP than plaque psoriasis.^3,4

Differential Diagnosis

There are many other cutaneous pustular diagnoses that must be ruled out when evaluating a patient with GPP (Table 1).²⁶ Acute generalized exanthematous pustulosis (AGEP) is a common mimicker of GPP that is differentiated histologically by the presence of eosinophils and necrotic keratinocytes.⁴ In addition to its distinct histopathologic findings, AGEP is classically associated with recent initiation of certain medications, most commonly penicillins, macrolides, quinolones, sulfonamides, terbinafine, and diltiazem.²⁷ In contrast, GPP more commonly is related to withdrawal of corticosteroids as well as initiation of some biologic medications, including anti-TNF agents.³ Generalized pustular psoriasis should be suspected over AGEP in patients with a personal or family history of psoriasis, though GPP may arise in patients with or without a history of psoriasis. Acute generalized exanthematous pustulosis usually is more abrupt in both onset and resolution compared with GPP, with clearance of pustules within a few days to weeks following cessation of the triggering factor.⁴

Other pustular variants of psoriasis (eg, palmoplantar pustular psoriasis, acrodermatitis continua of Hallopeau) are differentiated from GPP by their chronicity and localization to palmoplantar and/or ungual surfaces.⁵ Other differential diagnoses are listed in Table 1.

Diagnostic Criteria for GPP

Diagnostic criteria have been proposed for GPP (Table 2), including (1) the presence of sterile pustules, (2) systemic signs of inflammation, (3) laboratory abnormalities, (4) histopathologic confirmation of spongiform pustules of Kogoj, and (5) recurrence of symptoms.²² To definitively diagnose GPP, all 5 criteria must be met. To rule out mimickers, it may be worthwhile to perform Gram staining, potassium hydroxide preparation, in vitro cultures, and/or immunofluorescence testing.⁶

Treatment

Given the high potential for mortality associated with GPP, the most essential component of management is to ensure adequate supportive care. Any temperature, fluid, or electrolyte imbalances should be corrected as they arise. Secondary infections also must be identified and treated, if present, to reduce the risk for fatal complications, including systemic infection and sepsis. Precautions must be taken to ensure that serious end-organ damage, including hepatic, renal, and respiratory dysfunction, is avoided.

Adjunctive topical intervention often is initiated with bland emollients, corticosteroids, calcineurin inhibitors, and/or vitamin D derivatives to help soothe skin symptoms, but treatment with systemic therapies usually is warranted to achieve symptom control.^2,25 Importantly, there are no systemic or topical agents that have specifically been approved for the treatment of GPP in Europe or the United States.³ Given the absence of universally accepted treatment guidelines, therapeutic agents for GPP usually are selected based on clinical experience while also taking the extent of involvement and disease severity into consideration.³

Treatment Recommendations for Adults

Oral Systemic Agents—Treatment guidelines set forth by the National Psoriasis Foundation (NPF) in 2012 proposed that first-line therapies for GPP should be acitretin, cyclosporine, methotrexate, and infliximab.²⁸ However, since those guidelines were established, many new biologic therapies have been approved for the treatment of psoriasis and often are considered in the treatment of psoriasis subtypes, including GPP.²⁹ Although retinoids previously were considered to be a preferred first-line therapy, they are associated with a high incidence of adverse effects and must be used with caution in women of childbearing age.⁶ Oral acitretin at a dosage of 0.75 to 1.0 mg/kg/d has been shown to result in clinical improvement within 1 to 2 weeks, and a maintenance dosage of 0.125 to 0.25 mg/kg/d is required for several months to prevent recurrence.³⁰ Methotrexate—5.0 to 15.0 mg/wk, or perhaps higher in patients with refractory disease, increased by 2.5-mg intervals until symptoms improve—is recommended by the NPF in patients who are unresponsive or cannot tolerate retinoids, though close monitoring for hematologic abnormalities is required. Cyclosporine 2.5 to 5.0 mg/kg/d is considered an alternative to methotrexate and retinoids; it has a faster onset of action, with improvement reported as early as 2 weeks after initiation of therapy.^1,28 Although cyclosporine may be effective in the acute phase, especially in severe cases of GPP, long-term use of cyclosporine is not recommended because of the potential for renal dysfunction and hypertension.³¹

Biologic Agents—More recent evidence has accumulated supporting the efficacy of anti-TNF agents in the treatment of GPP, suggesting the positioning of these agents as first line. A number of case series have shown dramatic and rapid improvement of GPP with intravenous infliximab 3 to 5 mg/kg, with results observed hours to days after the first infusion.^32-37 Thus, infliximab is recommended as first-line treatment in severe acute cases, though its efficacy as a maintenance therapy has not been sufficiently investigated.⁶ Case reports and case series document the safety and efficacy of adalimumab 40 to 80 mg every 1 to 2 weeks^38,39 and etanercept 25 to 50 mg twice weekly^40-42 in patients with recalcitrantGPP. Therefore, these anti-TNF agents may be considered in patients who are nonresponsive to treatment with infliximab.

Rarely, there have been reports of paradoxical induction of GPP with the use of some anti-TNF agents,^43-45 which may be due to a cytokine imbalance characterized by unopposed IFN-α activation.⁶ In patients with a history of GPP after initiation of a biologic, treatment with agents from within the offending class should be avoided.

The IL-17A monoclonal antibodies secukinumab, ixekizumab, and brodalumab have been shown in open-label phase 3 studies to result in disease remission at 12 weeks.^46-48 Treatment with guselkumab, an IL-23 monoclonal antibody, also has demonstrated efficacy in patients with GPP.⁴⁹ Ustekinumab, an IL-12/23 inhibitor, in combination with acitretin also has been shown to be successful in achieving disease remission after a few weeks of treatment.⁵⁰

More recent case reports have shown the efficacy of IL-1 inhibitors including gevokizumab, canakinumab, and anakinra in achieving GPP clearance, though more prospective studies are needed to evaluate their efficacy.^51-53 Given the etiologic association between IL-1 disinhibition and GPP, future investigations of these therapies as well as those that target the IL-36 pathway may prove to be particularly interesting.

Phototherapy and Combination Therapies—Phototherapy may be considered as maintenance therapy after disease control is achieved, though it is not considered appropriate for acute cases.²⁸ Combination therapies with a biologic plus a nonbiologic systemic agent or alternating among various biologics may allow physicians to maximize benefits and minimize adverse effects in the long term, though there is insufficient evidence to suggest any specific combination treatment algorithm for GPP.²⁸

Treatment Recommendations for Pediatric Patients

Based on a small number of case series and case reports, the first-line treatment strategy for children with GPP is similar to adults. Given the notable adverse events of most oral systemic agents, biologic therapies may emerge as first-line therapy in the pediatric population as more evidence accumulates.²⁸

Treatment Recommendations for Pregnant Patients

Systemic corticosteroids are widely considered to be the first-line treatments for the management of impetigo herpetiformis.⁷ Low-dose prednisone (15–30 mg/d) usually is effective, but severe cases may require increasing the dosage to 60 mg/d.⁶ Given the potential for rebound flares upon withdrawal of systemic corticosteroids, these agents must be gradually tapered after the resolution of symptoms.

Certolizumab pegol also is an attractive option in pregnant patients with impetigo herpetiformis because of its favorable safety profile and negligible mother-to-infant transfer through the placenta or breast milk. It has been shown to be effective in treating GPP and impetigo herpetiformis during pregnancy in recently published case reports.^54,55 In refractory cases, other TNF-α inhibitors (eg, adalimumab, infliximab, etanercept) or cyclosporine may be considered. However, cautious medical monitoring is warranted, as little is known about the potential adverse effects of these agents to the mother and fetus.^28,56 Data from transplant recipients along with several case reports indicate that cyclosporine is not associated with an increased risk for adverse effects during pregnancy at a dose of 2 to 3 mg/kg.^57-59 Both methotrexate and retinoids are known teratogens and are therefore contraindicated in pregnant patients.⁵⁶

If pustules do not resolve in the postpartum period, patients should be treated with standard GPP therapies. However, long-term and population studies are lacking regarding the potential for infant exposure to systemic agents in breast milk. Therefore, the NPF recommends avoiding breastfeeding while taking systemic medications, if possible.⁵⁶

Limitations of Treatment Recommendations

The ability to generate an evidence-based treatment strategy for GPP is limited by a lack of high-quality studies investigating the efficacy and safety of treatments in patients with GPP due to the rarity and relapsing-remitting nature of the disease, which makes randomized controlled trials difficult to conduct. The quality of the available research is further limited by the lack of validated outcome measures to specifically assess improvements in patients with GPP, such that results are difficult to synthesize and compare among studies.³¹

Conclusion

Although limited, the available research suggests that treatment with various biologics, especially infliximab, is effective in achieving rapid clearance in patients with GPP. In general, biologics may be the most appropriate treatment option in patients with GPP given their relatively favorable safety profiles. Other oral systemic agents, including acitretin, cyclosporine, and methotrexate, have limited evidence to support their use in the acute phase, but their safety profiles often limit their utility in the long-term. Emerging evidence regarding the association of GPP with IL36RN mutations suggests a unique role for agents targeting the IL-36 or IL-1 pathways, though this has yet to be thoroughly investigated.

Acute generalized pustular psoriasis (GPP) is a rare severe variant of psoriasis characterized by the sudden widespread eruption of sterile pustules.^1,2 The cutaneous manifestations of GPP also may be accompanied by signs of systemic inflammation, including fever, malaise, and leukocytosis.² Complications are common and may be life-threatening, especially in older patients with comorbid diseases.³ Generalized pustular psoriasis most commonly occurs in patients with a preceding history of psoriasis, but it also may occur de novo.⁴ Generalized pustular psoriasis is associated with notable morbidity and mortality, and relapses are common.^3,4 Many triggers of GPP have been identified, including initiation and withdrawal of various medications, infections, pregnancy, and other conditions.^5,6 Although GPP most often occurs in adults, it also may arise in children and infants.³ In pregnancy, GPP is referred to as impetigo herpetiformis, despite having no etiologic ties with either herpes simplex virus or staphylococcal or streptococcal infection. Impetigo herpetiformis is considered one of the most dangerous dermatoses of pregnancy because of high rates of associated maternal and fetal morbidity.^6,7

Acute GPP has proven to be a challenging disease to treat due to the rarity and relapsing-remitting nature of the disease; additionally, there are relatively few randomized controlled trials investigating the efficacy and safety of treatments for GPP. This review summarizes the features of GPP, including the pathophysiology of the disease, clinical and histological manifestations, and recommendations for management based on a PubMed search of articles indexed for MEDLINE using MeSH terms pertaining to the disease, including generalized pustular psoriasis, impetigo herpetiformis, and von Zumbusch psoriasis.

Pathophysiology

The pathophysiology of GPP is only partially understood, but it is thought to have a distinct pattern of immune activation compared with plaque psoriasis.⁸ Although there is a considerable amount of overlap and cross-talk among cytokine pathways, GPP generally is driven by innate immunity and unrestrained IL-36 cytokine activity. In contrast, adaptive immune responses—namely the tumor necrosis factor (TNF) α, IL-23, IL-17, and IL-22 axes—underlie plaque psoriasis.^8-10

Proinflammatory IL-36 cytokines α, β, and γ, which are all part of the IL-1 superfamily, bind to the IL-36 receptor (IL-36R) to recruit and activate immune cells via various mediators, including IL-1β; IL-8; and chemokines CXCL1, CXCL2, and CXCL8.³ The IL-36 receptor antagonist (IL-36ra) acts to inhibit this inflammatory cascade.^3,8 Microarray analyses of skin biopsy samples have shown that overexpression of IL-17A, TNF-α, IL-1, and IL-36 are seen in both GPP and plaque psoriasis lesions, but GPP lesions had higher expression of IL-1β, IL-36α, and IL-36γ and elevated neutrophil chemokines—CXCL1, CXCL2, and CXCL8—compared with plaque psoriasis lesions.⁸

Gene Mutations Associated With GPP

There are 3 gene mutations that have been associated with pustular variants of psoriasis, though these mutations account for a minority of cases of GPP.⁴ Genetic screenings are not routinely indicated in patients with GPP, but they may be warranted in severe cases when a familial pattern of inheritance is suspected.⁴

IL36RN—The gene IL36RN codes the anti-inflammatory IL-36ra. Loss-of-function mutations in IL36RN lead to impairment of IL-36ra and consequently hyperactivity of the proinflammatory responses triggered by IL-36.³ Homozygous and heterozygous mutations in IL36RN have been observed in both familial and sporadic cases of GPP.^11-13 Subsequent retrospective analyses have identified the presence of IL36RN mutations in patients with GPP with frequencies ranging from 23% to 37%.^14-17IL36RN mutations are thought to be more common in patients without concomitant plaque psoriasis and have been associated with severe disease and early disease onset.¹⁵

CARD14—A gain-of-function mutation in CARD14 results in overactivation of the proinflammatory nuclear factor κB pathway and has been implicated in cases of GPP with concurrent psoriasis vulgaris. Interestingly, this may suggest distinct etiologies underlying GPP de novo and GPP in patients with a history of psoriasis.^18,19

AP1S3—A loss-of-function mutation in AP1S3 results in abnormal endosomal trafficking and autophagy as well as increased expression of IL-36α.^20,21

Clinical Presentation and DiagnosisCutaneous Manifestations of GPP

Generalized pustular psoriasis is characterized by the onset of widespread 2- to 3-mm sterile pustules on erythematous skin or within psoriasiform plaques⁴ (Figure). In patients with skin of color, the erythema may appear less obvious or perhaps slightly violaceous compared to White skin. Pustules may coalesce to form “lakes” of pus.⁵ Cutaneous symptoms include pain, burning, and pruritus. Associated mucosal findings may include cheilitis, geographic tongue, conjunctivitis, and uveitis.⁴

The severity of symptoms can vary greatly among patients as well as between flares within the same patient.^2,3 Four distinct patterns of GPP have been described. The von Zumbusch pattern is characterized by a rapid, generalized, painful, erythematous and pustular eruption accompanied by fever and asthenia. The pustules usually resolve after several days with extensive scaling. The annular pattern is characterized by annular, erythematous, scaly lesions with pustules present centrifugally. The lesions enlarge by centrifugal expansion over a period of hours to days, while healing occurs centrally. The exanthematic type is an acute eruption of small pustules that abruptly appear and disappear within a few days, usually from infection or medication initiation. Sometimes pustules appear within or at the edge of existing psoriatic plaques in a localized pattern—the fourth pattern—often following the exposure to irritants (eg, tars, anthralin).⁵

Impetigo Herpetiformis—Impetigo herpetiformis is a form of GPP associated with pregnancy. It generally presents early in the third trimester with symmetric erythematous plaques in flexural and intertriginous areas with pustules present at lesion margins. Lesions expand centrifugally, with pustulation present at the advancing edge.^6,7 Patients often are acutely ill with fever, delirium, vomiting, and tetany. Mucous membranes, including the tongue, mouth, and esophagus, also may be involved. The eruption typically resolves after delivery, though it often recurs with subsequent pregnancies, with the morbidity risk rising with each successive pregnancy.⁷

Systemic and Extracutaneous Manifestations of GPP

Although the severity of GPP is highly variable, skin manifestations often are accompanied by systemic manifestations of inflammation, including fever and malaise. Common laboratory abnormalities include leukocytosis with peripheral neutrophilia, a high serum C-reactive protein level, hypocalcemia, and hypoalbuminemia.²² Abnormal liver enzymes often are present and result from neutrophilic cholangitis, with alternating strictures and dilations of biliary ducts observed on magnetic resonance imaging.²³ Additional laboratory abnormalities are provided in Table 2. Other extracutaneous findings associated with GPP include arthralgia, edema, and characteristic psoriatic nail changes.⁴ Fatal complications include acute respiratory distress syndrome, renal dysfunction, cardiovascular shock, and sepsis.^24,25

Histologic Features

Given the potential for the skin manifestations of GPP to mimic other disorders, a skin biopsy is warranted to confirm the diagnosis. Generalized pustular psoriasis is histologically characterized by the presence of subcorneal macropustules (ie, spongiform pustules of Kogoj) formed by neutrophil infiltration into the spongelike network of the epidermis.⁶ Otherwise, the architecture of the epithelium in GPP is similar to that seen with plaque psoriasis, with parakeratosis, acanthosis, rete-ridge elongation, diminished stratum granulosum, and thinning of the suprapapillary epidermis, though the inflammatory cell infiltrate and edema are markedly more severe in GPP than plaque psoriasis.^3,4

Differential Diagnosis

There are many other cutaneous pustular diagnoses that must be ruled out when evaluating a patient with GPP (Table 1).²⁶ Acute generalized exanthematous pustulosis (AGEP) is a common mimicker of GPP that is differentiated histologically by the presence of eosinophils and necrotic keratinocytes.⁴ In addition to its distinct histopathologic findings, AGEP is classically associated with recent initiation of certain medications, most commonly penicillins, macrolides, quinolones, sulfonamides, terbinafine, and diltiazem.²⁷ In contrast, GPP more commonly is related to withdrawal of corticosteroids as well as initiation of some biologic medications, including anti-TNF agents.³ Generalized pustular psoriasis should be suspected over AGEP in patients with a personal or family history of psoriasis, though GPP may arise in patients with or without a history of psoriasis. Acute generalized exanthematous pustulosis usually is more abrupt in both onset and resolution compared with GPP, with clearance of pustules within a few days to weeks following cessation of the triggering factor.⁴

Other pustular variants of psoriasis (eg, palmoplantar pustular psoriasis, acrodermatitis continua of Hallopeau) are differentiated from GPP by their chronicity and localization to palmoplantar and/or ungual surfaces.⁵ Other differential diagnoses are listed in Table 1.

Diagnostic Criteria for GPP

Diagnostic criteria have been proposed for GPP (Table 2), including (1) the presence of sterile pustules, (2) systemic signs of inflammation, (3) laboratory abnormalities, (4) histopathologic confirmation of spongiform pustules of Kogoj, and (5) recurrence of symptoms.²² To definitively diagnose GPP, all 5 criteria must be met. To rule out mimickers, it may be worthwhile to perform Gram staining, potassium hydroxide preparation, in vitro cultures, and/or immunofluorescence testing.⁶

Treatment

Given the high potential for mortality associated with GPP, the most essential component of management is to ensure adequate supportive care. Any temperature, fluid, or electrolyte imbalances should be corrected as they arise. Secondary infections also must be identified and treated, if present, to reduce the risk for fatal complications, including systemic infection and sepsis. Precautions must be taken to ensure that serious end-organ damage, including hepatic, renal, and respiratory dysfunction, is avoided.

Adjunctive topical intervention often is initiated with bland emollients, corticosteroids, calcineurin inhibitors, and/or vitamin D derivatives to help soothe skin symptoms, but treatment with systemic therapies usually is warranted to achieve symptom control.^2,25 Importantly, there are no systemic or topical agents that have specifically been approved for the treatment of GPP in Europe or the United States.³ Given the absence of universally accepted treatment guidelines, therapeutic agents for GPP usually are selected based on clinical experience while also taking the extent of involvement and disease severity into consideration.³

Treatment Recommendations for Adults

Oral Systemic Agents—Treatment guidelines set forth by the National Psoriasis Foundation (NPF) in 2012 proposed that first-line therapies for GPP should be acitretin, cyclosporine, methotrexate, and infliximab.²⁸ However, since those guidelines were established, many new biologic therapies have been approved for the treatment of psoriasis and often are considered in the treatment of psoriasis subtypes, including GPP.²⁹ Although retinoids previously were considered to be a preferred first-line therapy, they are associated with a high incidence of adverse effects and must be used with caution in women of childbearing age.⁶ Oral acitretin at a dosage of 0.75 to 1.0 mg/kg/d has been shown to result in clinical improvement within 1 to 2 weeks, and a maintenance dosage of 0.125 to 0.25 mg/kg/d is required for several months to prevent recurrence.³⁰ Methotrexate—5.0 to 15.0 mg/wk, or perhaps higher in patients with refractory disease, increased by 2.5-mg intervals until symptoms improve—is recommended by the NPF in patients who are unresponsive or cannot tolerate retinoids, though close monitoring for hematologic abnormalities is required. Cyclosporine 2.5 to 5.0 mg/kg/d is considered an alternative to methotrexate and retinoids; it has a faster onset of action, with improvement reported as early as 2 weeks after initiation of therapy.^1,28 Although cyclosporine may be effective in the acute phase, especially in severe cases of GPP, long-term use of cyclosporine is not recommended because of the potential for renal dysfunction and hypertension.³¹

Biologic Agents—More recent evidence has accumulated supporting the efficacy of anti-TNF agents in the treatment of GPP, suggesting the positioning of these agents as first line. A number of case series have shown dramatic and rapid improvement of GPP with intravenous infliximab 3 to 5 mg/kg, with results observed hours to days after the first infusion.^32-37 Thus, infliximab is recommended as first-line treatment in severe acute cases, though its efficacy as a maintenance therapy has not been sufficiently investigated.⁶ Case reports and case series document the safety and efficacy of adalimumab 40 to 80 mg every 1 to 2 weeks^38,39 and etanercept 25 to 50 mg twice weekly^40-42 in patients with recalcitrantGPP. Therefore, these anti-TNF agents may be considered in patients who are nonresponsive to treatment with infliximab.

Rarely, there have been reports of paradoxical induction of GPP with the use of some anti-TNF agents,^43-45 which may be due to a cytokine imbalance characterized by unopposed IFN-α activation.⁶ In patients with a history of GPP after initiation of a biologic, treatment with agents from within the offending class should be avoided.

The IL-17A monoclonal antibodies secukinumab, ixekizumab, and brodalumab have been shown in open-label phase 3 studies to result in disease remission at 12 weeks.^46-48 Treatment with guselkumab, an IL-23 monoclonal antibody, also has demonstrated efficacy in patients with GPP.⁴⁹ Ustekinumab, an IL-12/23 inhibitor, in combination with acitretin also has been shown to be successful in achieving disease remission after a few weeks of treatment.⁵⁰

More recent case reports have shown the efficacy of IL-1 inhibitors including gevokizumab, canakinumab, and anakinra in achieving GPP clearance, though more prospective studies are needed to evaluate their efficacy.^51-53 Given the etiologic association between IL-1 disinhibition and GPP, future investigations of these therapies as well as those that target the IL-36 pathway may prove to be particularly interesting.

Phototherapy and Combination Therapies—Phototherapy may be considered as maintenance therapy after disease control is achieved, though it is not considered appropriate for acute cases.²⁸ Combination therapies with a biologic plus a nonbiologic systemic agent or alternating among various biologics may allow physicians to maximize benefits and minimize adverse effects in the long term, though there is insufficient evidence to suggest any specific combination treatment algorithm for GPP.²⁸

Treatment Recommendations for Pediatric Patients

Based on a small number of case series and case reports, the first-line treatment strategy for children with GPP is similar to adults. Given the notable adverse events of most oral systemic agents, biologic therapies may emerge as first-line therapy in the pediatric population as more evidence accumulates.²⁸

Treatment Recommendations for Pregnant Patients

Systemic corticosteroids are widely considered to be the first-line treatments for the management of impetigo herpetiformis.⁷ Low-dose prednisone (15–30 mg/d) usually is effective, but severe cases may require increasing the dosage to 60 mg/d.⁶ Given the potential for rebound flares upon withdrawal of systemic corticosteroids, these agents must be gradually tapered after the resolution of symptoms.

Certolizumab pegol also is an attractive option in pregnant patients with impetigo herpetiformis because of its favorable safety profile and negligible mother-to-infant transfer through the placenta or breast milk. It has been shown to be effective in treating GPP and impetigo herpetiformis during pregnancy in recently published case reports.^54,55 In refractory cases, other TNF-α inhibitors (eg, adalimumab, infliximab, etanercept) or cyclosporine may be considered. However, cautious medical monitoring is warranted, as little is known about the potential adverse effects of these agents to the mother and fetus.^28,56 Data from transplant recipients along with several case reports indicate that cyclosporine is not associated with an increased risk for adverse effects during pregnancy at a dose of 2 to 3 mg/kg.^57-59 Both methotrexate and retinoids are known teratogens and are therefore contraindicated in pregnant patients.⁵⁶

If pustules do not resolve in the postpartum period, patients should be treated with standard GPP therapies. However, long-term and population studies are lacking regarding the potential for infant exposure to systemic agents in breast milk. Therefore, the NPF recommends avoiding breastfeeding while taking systemic medications, if possible.⁵⁶

Limitations of Treatment Recommendations

The ability to generate an evidence-based treatment strategy for GPP is limited by a lack of high-quality studies investigating the efficacy and safety of treatments in patients with GPP due to the rarity and relapsing-remitting nature of the disease, which makes randomized controlled trials difficult to conduct. The quality of the available research is further limited by the lack of validated outcome measures to specifically assess improvements in patients with GPP, such that results are difficult to synthesize and compare among studies.³¹

Conclusion

Although limited, the available research suggests that treatment with various biologics, especially infliximab, is effective in achieving rapid clearance in patients with GPP. In general, biologics may be the most appropriate treatment option in patients with GPP given their relatively favorable safety profiles. Other oral systemic agents, including acitretin, cyclosporine, and methotrexate, have limited evidence to support their use in the acute phase, but their safety profiles often limit their utility in the long-term. Emerging evidence regarding the association of GPP with IL36RN mutations suggests a unique role for agents targeting the IL-36 or IL-1 pathways, though this has yet to be thoroughly investigated.

Acute generalized pustular psoriasis (GPP) is a rare severe variant of psoriasis characterized by the sudden widespread eruption of sterile pustules.^1,2 The cutaneous manifestations of GPP also may be accompanied by signs of systemic inflammation, including fever, malaise, and leukocytosis.² Complications are common and may be life-threatening, especially in older patients with comorbid diseases.³ Generalized pustular psoriasis most commonly occurs in patients with a preceding history of psoriasis, but it also may occur de novo.⁴ Generalized pustular psoriasis is associated with notable morbidity and mortality, and relapses are common.^3,4 Many triggers of GPP have been identified, including initiation and withdrawal of various medications, infections, pregnancy, and other conditions.^5,6 Although GPP most often occurs in adults, it also may arise in children and infants.³ In pregnancy, GPP is referred to as impetigo herpetiformis, despite having no etiologic ties with either herpes simplex virus or staphylococcal or streptococcal infection. Impetigo herpetiformis is considered one of the most dangerous dermatoses of pregnancy because of high rates of associated maternal and fetal morbidity.^6,7

Acute GPP has proven to be a challenging disease to treat due to the rarity and relapsing-remitting nature of the disease; additionally, there are relatively few randomized controlled trials investigating the efficacy and safety of treatments for GPP. This review summarizes the features of GPP, including the pathophysiology of the disease, clinical and histological manifestations, and recommendations for management based on a PubMed search of articles indexed for MEDLINE using MeSH terms pertaining to the disease, including generalized pustular psoriasis, impetigo herpetiformis, and von Zumbusch psoriasis.

Pathophysiology

The pathophysiology of GPP is only partially understood, but it is thought to have a distinct pattern of immune activation compared with plaque psoriasis.⁸ Although there is a considerable amount of overlap and cross-talk among cytokine pathways, GPP generally is driven by innate immunity and unrestrained IL-36 cytokine activity. In contrast, adaptive immune responses—namely the tumor necrosis factor (TNF) α, IL-23, IL-17, and IL-22 axes—underlie plaque psoriasis.^8-10

Proinflammatory IL-36 cytokines α, β, and γ, which are all part of the IL-1 superfamily, bind to the IL-36 receptor (IL-36R) to recruit and activate immune cells via various mediators, including IL-1β; IL-8; and chemokines CXCL1, CXCL2, and CXCL8.³ The IL-36 receptor antagonist (IL-36ra) acts to inhibit this inflammatory cascade.^3,8 Microarray analyses of skin biopsy samples have shown that overexpression of IL-17A, TNF-α, IL-1, and IL-36 are seen in both GPP and plaque psoriasis lesions, but GPP lesions had higher expression of IL-1β, IL-36α, and IL-36γ and elevated neutrophil chemokines—CXCL1, CXCL2, and CXCL8—compared with plaque psoriasis lesions.⁸

Gene Mutations Associated With GPP

There are 3 gene mutations that have been associated with pustular variants of psoriasis, though these mutations account for a minority of cases of GPP.⁴ Genetic screenings are not routinely indicated in patients with GPP, but they may be warranted in severe cases when a familial pattern of inheritance is suspected.⁴

IL36RN—The gene IL36RN codes the anti-inflammatory IL-36ra. Loss-of-function mutations in IL36RN lead to impairment of IL-36ra and consequently hyperactivity of the proinflammatory responses triggered by IL-36.³ Homozygous and heterozygous mutations in IL36RN have been observed in both familial and sporadic cases of GPP.^11-13 Subsequent retrospective analyses have identified the presence of IL36RN mutations in patients with GPP with frequencies ranging from 23% to 37%.^14-17IL36RN mutations are thought to be more common in patients without concomitant plaque psoriasis and have been associated with severe disease and early disease onset.¹⁵

CARD14—A gain-of-function mutation in CARD14 results in overactivation of the proinflammatory nuclear factor κB pathway and has been implicated in cases of GPP with concurrent psoriasis vulgaris. Interestingly, this may suggest distinct etiologies underlying GPP de novo and GPP in patients with a history of psoriasis.^18,19

AP1S3—A loss-of-function mutation in AP1S3 results in abnormal endosomal trafficking and autophagy as well as increased expression of IL-36α.^20,21

Clinical Presentation and DiagnosisCutaneous Manifestations of GPP

Generalized pustular psoriasis is characterized by the onset of widespread 2- to 3-mm sterile pustules on erythematous skin or within psoriasiform plaques⁴ (Figure). In patients with skin of color, the erythema may appear less obvious or perhaps slightly violaceous compared to White skin. Pustules may coalesce to form “lakes” of pus.⁵ Cutaneous symptoms include pain, burning, and pruritus. Associated mucosal findings may include cheilitis, geographic tongue, conjunctivitis, and uveitis.⁴

The severity of symptoms can vary greatly among patients as well as between flares within the same patient.^2,3 Four distinct patterns of GPP have been described. The von Zumbusch pattern is characterized by a rapid, generalized, painful, erythematous and pustular eruption accompanied by fever and asthenia. The pustules usually resolve after several days with extensive scaling. The annular pattern is characterized by annular, erythematous, scaly lesions with pustules present centrifugally. The lesions enlarge by centrifugal expansion over a period of hours to days, while healing occurs centrally. The exanthematic type is an acute eruption of small pustules that abruptly appear and disappear within a few days, usually from infection or medication initiation. Sometimes pustules appear within or at the edge of existing psoriatic plaques in a localized pattern—the fourth pattern—often following the exposure to irritants (eg, tars, anthralin).⁵

Impetigo Herpetiformis—Impetigo herpetiformis is a form of GPP associated with pregnancy. It generally presents early in the third trimester with symmetric erythematous plaques in flexural and intertriginous areas with pustules present at lesion margins. Lesions expand centrifugally, with pustulation present at the advancing edge.^6,7 Patients often are acutely ill with fever, delirium, vomiting, and tetany. Mucous membranes, including the tongue, mouth, and esophagus, also may be involved. The eruption typically resolves after delivery, though it often recurs with subsequent pregnancies, with the morbidity risk rising with each successive pregnancy.⁷

Systemic and Extracutaneous Manifestations of GPP

Although the severity of GPP is highly variable, skin manifestations often are accompanied by systemic manifestations of inflammation, including fever and malaise. Common laboratory abnormalities include leukocytosis with peripheral neutrophilia, a high serum C-reactive protein level, hypocalcemia, and hypoalbuminemia.²² Abnormal liver enzymes often are present and result from neutrophilic cholangitis, with alternating strictures and dilations of biliary ducts observed on magnetic resonance imaging.²³ Additional laboratory abnormalities are provided in Table 2. Other extracutaneous findings associated with GPP include arthralgia, edema, and characteristic psoriatic nail changes.⁴ Fatal complications include acute respiratory distress syndrome, renal dysfunction, cardiovascular shock, and sepsis.^24,25

Histologic Features

Given the potential for the skin manifestations of GPP to mimic other disorders, a skin biopsy is warranted to confirm the diagnosis. Generalized pustular psoriasis is histologically characterized by the presence of subcorneal macropustules (ie, spongiform pustules of Kogoj) formed by neutrophil infiltration into the spongelike network of the epidermis.⁶ Otherwise, the architecture of the epithelium in GPP is similar to that seen with plaque psoriasis, with parakeratosis, acanthosis, rete-ridge elongation, diminished stratum granulosum, and thinning of the suprapapillary epidermis, though the inflammatory cell infiltrate and edema are markedly more severe in GPP than plaque psoriasis.^3,4

Differential Diagnosis

There are many other cutaneous pustular diagnoses that must be ruled out when evaluating a patient with GPP (Table 1).²⁶ Acute generalized exanthematous pustulosis (AGEP) is a common mimicker of GPP that is differentiated histologically by the presence of eosinophils and necrotic keratinocytes.⁴ In addition to its distinct histopathologic findings, AGEP is classically associated with recent initiation of certain medications, most commonly penicillins, macrolides, quinolones, sulfonamides, terbinafine, and diltiazem.²⁷ In contrast, GPP more commonly is related to withdrawal of corticosteroids as well as initiation of some biologic medications, including anti-TNF agents.³ Generalized pustular psoriasis should be suspected over AGEP in patients with a personal or family history of psoriasis, though GPP may arise in patients with or without a history of psoriasis. Acute generalized exanthematous pustulosis usually is more abrupt in both onset and resolution compared with GPP, with clearance of pustules within a few days to weeks following cessation of the triggering factor.⁴

Other pustular variants of psoriasis (eg, palmoplantar pustular psoriasis, acrodermatitis continua of Hallopeau) are differentiated from GPP by their chronicity and localization to palmoplantar and/or ungual surfaces.⁵ Other differential diagnoses are listed in Table 1.

Diagnostic Criteria for GPP

Diagnostic criteria have been proposed for GPP (Table 2), including (1) the presence of sterile pustules, (2) systemic signs of inflammation, (3) laboratory abnormalities, (4) histopathologic confirmation of spongiform pustules of Kogoj, and (5) recurrence of symptoms.²² To definitively diagnose GPP, all 5 criteria must be met. To rule out mimickers, it may be worthwhile to perform Gram staining, potassium hydroxide preparation, in vitro cultures, and/or immunofluorescence testing.⁶

Treatment

Given the high potential for mortality associated with GPP, the most essential component of management is to ensure adequate supportive care. Any temperature, fluid, or electrolyte imbalances should be corrected as they arise. Secondary infections also must be identified and treated, if present, to reduce the risk for fatal complications, including systemic infection and sepsis. Precautions must be taken to ensure that serious end-organ damage, including hepatic, renal, and respiratory dysfunction, is avoided.

Adjunctive topical intervention often is initiated with bland emollients, corticosteroids, calcineurin inhibitors, and/or vitamin D derivatives to help soothe skin symptoms, but treatment with systemic therapies usually is warranted to achieve symptom control.^2,25 Importantly, there are no systemic or topical agents that have specifically been approved for the treatment of GPP in Europe or the United States.³ Given the absence of universally accepted treatment guidelines, therapeutic agents for GPP usually are selected based on clinical experience while also taking the extent of involvement and disease severity into consideration.³

Treatment Recommendations for Adults

Oral Systemic Agents—Treatment guidelines set forth by the National Psoriasis Foundation (NPF) in 2012 proposed that first-line therapies for GPP should be acitretin, cyclosporine, methotrexate, and infliximab.²⁸ However, since those guidelines were established, many new biologic therapies have been approved for the treatment of psoriasis and often are considered in the treatment of psoriasis subtypes, including GPP.²⁹ Although retinoids previously were considered to be a preferred first-line therapy, they are associated with a high incidence of adverse effects and must be used with caution in women of childbearing age.⁶ Oral acitretin at a dosage of 0.75 to 1.0 mg/kg/d has been shown to result in clinical improvement within 1 to 2 weeks, and a maintenance dosage of 0.125 to 0.25 mg/kg/d is required for several months to prevent recurrence.³⁰ Methotrexate—5.0 to 15.0 mg/wk, or perhaps higher in patients with refractory disease, increased by 2.5-mg intervals until symptoms improve—is recommended by the NPF in patients who are unresponsive or cannot tolerate retinoids, though close monitoring for hematologic abnormalities is required. Cyclosporine 2.5 to 5.0 mg/kg/d is considered an alternative to methotrexate and retinoids; it has a faster onset of action, with improvement reported as early as 2 weeks after initiation of therapy.^1,28 Although cyclosporine may be effective in the acute phase, especially in severe cases of GPP, long-term use of cyclosporine is not recommended because of the potential for renal dysfunction and hypertension.³¹

Biologic Agents—More recent evidence has accumulated supporting the efficacy of anti-TNF agents in the treatment of GPP, suggesting the positioning of these agents as first line. A number of case series have shown dramatic and rapid improvement of GPP with intravenous infliximab 3 to 5 mg/kg, with results observed hours to days after the first infusion.^32-37 Thus, infliximab is recommended as first-line treatment in severe acute cases, though its efficacy as a maintenance therapy has not been sufficiently investigated.⁶ Case reports and case series document the safety and efficacy of adalimumab 40 to 80 mg every 1 to 2 weeks^38,39 and etanercept 25 to 50 mg twice weekly^40-42 in patients with recalcitrantGPP. Therefore, these anti-TNF agents may be considered in patients who are nonresponsive to treatment with infliximab.

Rarely, there have been reports of paradoxical induction of GPP with the use of some anti-TNF agents,^43-45 which may be due to a cytokine imbalance characterized by unopposed IFN-α activation.⁶ In patients with a history of GPP after initiation of a biologic, treatment with agents from within the offending class should be avoided.

The IL-17A monoclonal antibodies secukinumab, ixekizumab, and brodalumab have been shown in open-label phase 3 studies to result in disease remission at 12 weeks.^46-48 Treatment with guselkumab, an IL-23 monoclonal antibody, also has demonstrated efficacy in patients with GPP.⁴⁹ Ustekinumab, an IL-12/23 inhibitor, in combination with acitretin also has been shown to be successful in achieving disease remission after a few weeks of treatment.⁵⁰

More recent case reports have shown the efficacy of IL-1 inhibitors including gevokizumab, canakinumab, and anakinra in achieving GPP clearance, though more prospective studies are needed to evaluate their efficacy.^51-53 Given the etiologic association between IL-1 disinhibition and GPP, future investigations of these therapies as well as those that target the IL-36 pathway may prove to be particularly interesting.

Phototherapy and Combination Therapies—Phototherapy may be considered as maintenance therapy after disease control is achieved, though it is not considered appropriate for acute cases.²⁸ Combination therapies with a biologic plus a nonbiologic systemic agent or alternating among various biologics may allow physicians to maximize benefits and minimize adverse effects in the long term, though there is insufficient evidence to suggest any specific combination treatment algorithm for GPP.²⁸

Treatment Recommendations for Pediatric Patients

Based on a small number of case series and case reports, the first-line treatment strategy for children with GPP is similar to adults. Given the notable adverse events of most oral systemic agents, biologic therapies may emerge as first-line therapy in the pediatric population as more evidence accumulates.²⁸

Treatment Recommendations for Pregnant Patients

Systemic corticosteroids are widely considered to be the first-line treatments for the management of impetigo herpetiformis.⁷ Low-dose prednisone (15–30 mg/d) usually is effective, but severe cases may require increasing the dosage to 60 mg/d.⁶ Given the potential for rebound flares upon withdrawal of systemic corticosteroids, these agents must be gradually tapered after the resolution of symptoms.

Certolizumab pegol also is an attractive option in pregnant patients with impetigo herpetiformis because of its favorable safety profile and negligible mother-to-infant transfer through the placenta or breast milk. It has been shown to be effective in treating GPP and impetigo herpetiformis during pregnancy in recently published case reports.^54,55 In refractory cases, other TNF-α inhibitors (eg, adalimumab, infliximab, etanercept) or cyclosporine may be considered. However, cautious medical monitoring is warranted, as little is known about the potential adverse effects of these agents to the mother and fetus.^28,56 Data from transplant recipients along with several case reports indicate that cyclosporine is not associated with an increased risk for adverse effects during pregnancy at a dose of 2 to 3 mg/kg.^57-59 Both methotrexate and retinoids are known teratogens and are therefore contraindicated in pregnant patients.⁵⁶

If pustules do not resolve in the postpartum period, patients should be treated with standard GPP therapies. However, long-term and population studies are lacking regarding the potential for infant exposure to systemic agents in breast milk. Therefore, the NPF recommends avoiding breastfeeding while taking systemic medications, if possible.⁵⁶

Limitations of Treatment Recommendations

The ability to generate an evidence-based treatment strategy for GPP is limited by a lack of high-quality studies investigating the efficacy and safety of treatments in patients with GPP due to the rarity and relapsing-remitting nature of the disease, which makes randomized controlled trials difficult to conduct. The quality of the available research is further limited by the lack of validated outcome measures to specifically assess improvements in patients with GPP, such that results are difficult to synthesize and compare among studies.³¹

Conclusion

Although limited, the available research suggests that treatment with various biologics, especially infliximab, is effective in achieving rapid clearance in patients with GPP. In general, biologics may be the most appropriate treatment option in patients with GPP given their relatively favorable safety profiles. Other oral systemic agents, including acitretin, cyclosporine, and methotrexate, have limited evidence to support their use in the acute phase, but their safety profiles often limit their utility in the long-term. Emerging evidence regarding the association of GPP with IL36RN mutations suggests a unique role for agents targeting the IL-36 or IL-1 pathways, though this has yet to be thoroughly investigated.

Psoriasis is a chronic inflammatory skin disease characterized by erythematous scaly plaques that can invoke substantial pain, pruritus, and quality-of-life disturbance in patients. Topical therapies are the most commonly used medications for treating psoriasis, with one study (N = 128,308) showing that more than 85% of patients with psoriasis were managed solely with topical medications. ¹ For patients with mild to moderate psoriasis, topical agents alone may be able to control disease completely. For those with more severe disease, topical agents are used adjunctively with systemic or biologic agents to optimize disease control in localized areas.

The American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) published guidelines in 2020 for managing psoriasis with topical agents in adults.² This review presents the most up-to-date clinical recommendations for topical agent use in adult patients with psoriasis and elaborates on each drug’s pharmacologic and safety profile. Specifically, evidence-based treatment recommendations for topical steroids, calcineurin inhibitors (CNIs), vitamin D analogues, retinoids (tazarotene), emollients, keratolytics (salicylic acid), anthracenes (anthralin), and keratoplastics (coal tar) will be addressed (Table 1). Recommendations for combination therapy with other treatment modalities including UVB light therapy, biologics, and systemic nonbiologic agents also will be discussed.

Selecting a Topical Agent Based on Disease Localization

When treating patients with psoriasis with topical therapies, clinicians should take into consideration drug potency, as it determines how effective a treatment will be in penetrating the skin barrier. Plaque characteristics, such as distribution (localized vs widespread), anatomical localization (flexural, scalp, palms/soles/nails), size (large vs small), and thickness (thick vs thin), not only influence treatment effectiveness but also the incidence of drug-related adverse events. Furthermore, preferred topical therapies are tailored to each patient based on disease characteristics and activity. Coal tar and anthralin have been used less frequently than other topical therapies for psoriasis because of their undesirable side-effect profiles (Table 1).³

Face and Intertriginous Regions—The face and intertriginous areas are sensitive because skin tends to be thin in these regions. Emollients are recommended for disease in these locations given their safety and flexibility in use for most areas. Conversely, anthralin should be avoided on the face, intertriginous areas, and even highly visible locations because of the potential for skin staining. Low-potency corticosteroids also have utility in psoriasis distributed on the face and intertriginous regions. Additionally, application of steroids around the eyes should be cautioned because topical steroids can induce ocular complications such as glaucoma and cataracts in rare circumstances.⁴

Off-label use of CNIs for psoriasis on the face and intertriginous areas also is effective. Currently, there is a level B recommendation for off-label use of 0.1% tacrolimus for up to 8 weeks for inverse psoriasis or psoriasis on the face. Off-label use of pimecrolimus for 4 to 8 weeks also can be considered for inverse psoriasis. Combination therapy consisting of hydrocortisone with calcipotriol ointment is another effective regimen.⁵ One study also suggested that use of crisaborole for 4 to 8 weeks in intertriginous psoriasis can be effective and well tolerated.⁶

Scalp—The vehicle of medication administration is especially important in hair-bearing areas such as the scalp, as these areas are challenging for medication application and patient adherence. Thus, patient preferences for the vehicle must be considered. Several studies have been conducted to assess preference for various vehicles in scalp psoriasis. A foam or solution may be preferable to ointments, gels, or creams.⁷ Gels may be preferred over ointments.⁸ There is a level A recommendation supporting the use of class 1 to 7 topical steroids for a minimum of 4 weeks as initial and maintenance treatment of scalp psoriasis. The highest level of evidence (level A) also supports the use of calcipotriol foam or combination therapy of calcipotriol–betamethasone dipropionate gel for 4 to 12 weeks as treatment of mild to moderate scalp psoriasis.

Nails—Several options for topical medications have been recommended for the treatment of nail psoriasis. Currently, there is a level B recommendation for the use of tazarotene for the treatment of nail psoriasis. Another effective regimen is combination therapy with vitamin D analogues and betamethasone dipropionate.⁹ Topical steroid use for nail psoriasis should be limited to 12 weeks because of the risk for bone atrophy with chronic steroid use.

Palmoplantar—The palms and soles have a thicker epidermal layer than other areas of the body. As a result, class 1 corticosteroids can be used for palmoplantar psoriasis for more than 4 weeks with vigilant monitoring for adverse effects such as skin atrophy, tachyphylaxis, or tinea infection. Tazarotene also has been shown to be helpful in treating palmoplantar psoriasis.

Resistant Disease—Intralesional steroids are beneficial treatment options for recalcitrant psoriasis in glabrous areas, as well as for palmoplantar, nail, and scalp psoriasis. Up to 10 mg/mL of triamcinolone acetonide used every 3 to 4 weeks is an effective regimen.¹⁰Pregnancy/Breastfeeding—Women of childbearing potential have additional safety precautions that should be considered during medication selection. Emollients have been shown to be safe during pregnancy and lactation. Currently, there is little known about CNI use during pregnancy. During lactation, CNIs can be used by breastfeeding mothers in most areas, excluding the breasts. Evaluation of the safety of anthralin and vitamin D analogues during pregnancy and lactation have not been studied. For these agents, dermatologists need to use their clinical judgment to weigh the risks and benefits of medication, particularly in patients requiring occlusion, higher medication doses, or treatment over a large surface area. Salicylic acid should be used with caution in pregnant and breastfeeding mothers because it is a pregnancy category C drug. Lower-potency corticosteroids may be used with caution during pregnancy and breastfeeding. More potent corticosteroids and coal tar, however, should be avoided. Similarly, tazarotene use is contraindicated in pregnancy. According to the US Food and Drug Administration labels for all forms of topical tazarotene, a pregnancy test must be obtained 2 weeks prior to tazarotene treatment initiation in women of childbearing potential because of the risk for serious fetal malformations and toxicity.

Recommendations, Risks, and Benefits of Topical Therapy for the Management of Psoriasis

Topical Corticosteroids—Topical corticosteroids (TCs) are widely used for inflammatory skin conditions and are available in a variety of strengths (Table 2). They are thought to exert their action by regulating the gene transcription of proinflammatory mediators. For psoriasis, steroids are recommended for 2 to 4 weeks, depending on disease severity. Although potent and superpotent steroids are more effective than mild- to moderate-strength TCs, use of lower-potency TCs may be warranted depending on disease distribution and localization.¹¹ For treatment of psoriasis with no involvement of the intertriginous areas, use of class 1 to 5 TCs for up to 4 weeks is recommended.

For moderate to severe psoriasis with 20% or less body surface area (BSA) affected, combination therapy consisting of mometasone and salicylic acid has been shown to be more effective than mometasone alone.^12,13 There currently is a level A recommendation for the use of combination therapy with class 1 TCs and etanercept for 12 weeks in patients with moderate to severe psoriasis who require both systemic and topical therapies for disease control. Similarly, combination therapy with infliximab and high-potency TCs has a level B recommendation to enhance efficacy for the treatment of moderate to severe psoriasis.¹⁴ High-quality studies on the use of TCs with anti–IL-12/IL-23, anti–IL-23, and anti–IL-17 currently are unavailable, but the combination is not expected to be unsafe.^14,15 Combination therapy of betamethasone dipropionate ointment and low-dose cyclosporine is an alternative regimen with a level B recommendation.

The most common adverse effects with use of TCs are skin thinning and atrophy, telangiectasia, and striae (Table 1). With clinical improvement of disease, it is recommended that clinicians taper TCs to prevent rebound effect. To decrease TC-related adverse effects, clinicians should use combination therapy with steroid-sparing agents for disease maintenance, transition to lower-potency corticosteroids, or use intermittent steroid therapy. Systemic effects of TC use include hypothalamic-pituitary-adrenal axis suppression, Cushing syndrome, and osteonecrosis of the femoral head.^16-18 These systemic effects with TC use are rare unless treatment is for disease involving greater than 20% BSA or occlusion for more than 4 weeks.

Calcineurin Inhibitors—Calcineurin inhibitors inhibit calcineurin phosphorylation and T-cell activation, subsequently decreasing the expression of proinflammatory cytokines. Currently, they are not approved by the US Food and Drug Administration to treat psoriasis but have demonstrated efficacy in randomized control trials (RCTs) for facial and intertriginous psoriasis. In RCTs, 71% of patients using pimecrolimus cream 0.1% twice daily for 8 weeks achieved an investigator global assessment score of clear (0) or almost clear (1) compared with 21% of placebo-treated patients (N=57).¹⁹ Other trials have shown that 65% of patients receiving tacrolimus ointment 0.1% for 8 weeks achieved an investigator global assessment score of 0 or 1 compared with 31% of placebo-treated patients (N=167).²⁰ Because of their efficacy in RCTs, CNIs commonly are used off label to treat psoriasis.

The most common adverse effects with CNI use are burning, pruritus, and flushing with alcohol ingestion (Table 1). Additionally, CNIs have a black box warning that use may increase the risk for malignancy, but this risk has not been demonstrated with topical use in humans.²¹Vitamin D Analogues—The class of vitamin D analogues—calcipotriol/calcipotriene and calcitriol—frequently are used to treat psoriasis. Vitamin D analogues exert their beneficial effects by inhibiting keratinocyte proliferation and enhancing keratinocyte differentiation. They also are ideal for long-term use (up to 52 weeks) in mild to moderate psoriasis and can be used in combination with class 2 and 3 TCs. There is a level A recommendation that supports the use of combination therapy with calcipotriol and TCs for the treatment of mild to moderate psoriasis.

For severe psoriasis, many studies have investigated the efficacy of combination therapy with vitamin D analogues and systemic treatments. Combination therapy with calcipotriol and methotrexate or calcipotriol and acitretin are effective treatment regimens with level A recommendations. Calcipotriol–betamethasone dipropionate ointment in combination with low-dose cyclosporine is an alternative option with a level B recommendation. Because vitamin D analogues are inactivated by UVA and UVB radiation, clinicians should advise their patients to use vitamin D analogues after receiving UVB phototherapy.²²

Common adverse effects of vitamin D analogues include burning, pruritus, erythema, and dryness (Table 1). Hypercalcemia and parathyroid hormone suppression are extremely rare unless treatment occurs over a large surface area (>30% BSA) or the patient has concurrent renal disease or impairments in calcium metabolism.

Tazarotene—Tazarotene is a topical retinoid that acts by decreasing keratinocyte proliferation, facilitating keratinocyte differentiation, and inhibiting inflammation. Patients with mild to moderate psoriasis are recommended to receive tazarotene treatment for 8 to 12 weeks. In several RCTs, tazarotene gel 0.1% and tazarotene cream 0.1% and 0.05% achieved treatment success in treating plaque psoriasis.^23,24

For increased efficacy, clinicians can recommend combination therapy with tazarotene and a TC. Combination therapy with tazarotene and a mid- or high-potency TC for 8 to 16 weeks has been shown to be more effective than treatment with tazarotene alone.²⁵ Thus, there is a level A recommendation for use of this combination to treat mild to moderate psoriasis. Agents used in combination therapy work synergistically to decrease the length of treatment and increase the duration of remission. The frequency of adverse effects, such as irritation from tazarotene and skin atrophy from TCs, also are reduced.²⁶ Combination therapy with tazarotene and narrowband UVB (NB-UVB) is another effective option that requires less UV radiation than NB-UVB alone because of the synergistic effects of both treatment modalities.²⁷ Clinicians should counsel patients on the adverse effects of tazarotene, which include local irritation, burning, pruritus, and erythema (Table 1).

Emollients—Emollients are nonmedicated moisturizers that decrease the amount of transepidermal water loss. There is a level B recommendation for use of emollients and TCs in combination for 4 to 8 weeks to treat psoriasis. In fact, combination therapy with mometasone and emollients has demonstrated greater improvement in symptoms of palmoplantar psoriasis (ie, erythema, desquamation, infiltration, BSA involvement) than mometasone alone.²⁸ Emollients are safe options that can be used on all areas of the body and during pregnancy and lactation. Although adverse effects of emollients are rare, clinicians should counsel patients on the risk for contact dermatitis if specific allergies to ingredients/fragrances exist (Table 1).

Salicylic Acid—Salicylic acid is a topical keratolytic that can be used to treat psoriatic plaques. Use of salicylic acid for 8 to 16 weeks has been shown to be effective for mild to moderate psoriasis. Combination therapy of salicylic acid and TCs in patients with 20% or less BSA affected is a safe and effective option with a level B recommendation. Combination therapy with salicylic acid and calcipotriene, however, should be avoided because calcipotriene is inactivated by salicylic acid. It also is recommended that salicylic acid application follow phototherapy when both treatment modalities are used in combination.^29,30 Clinicians should be cautious about using salicylic acid in patients with renal or hepatic disease because of the increased risk for salicylate toxicity (Table 1).

Anthralin—Anthralin is a synthetic hydrocarbon derivative that has been shown to reduce inflammation and normalize keratinocyte proliferation through an unknown mechanism. It is recommended that patients with mild to moderate psoriasis receive anthralin treatment for 8 to 12 weeks, with a maximum application time of 2 hours per day. Combination therapy of excimer laser and anthralin has been shown to be more effective in treating psoriasis than anthralin alone.³¹ Therefore, clinicians have the option of including excimer laser therapy for additional disease control. Anthralin should be avoided on the face, flexural regions, and highly visible areas because of potential skin staining (Table 1). Other adverse effects include application-site burning and erythema.

Coal Tar—Coal tar is a heterogenous mixture of aromatic hydrocarbons that is an effective treatment of psoriasis because of its inherent anti-inflammatory and keratoplastic properties. There is high-quality evidence supporting a level A recommendation for coal tar use in mild to moderate psoriasis. Combination therapy with NB-UVB and coal tar (also known as Goeckerman therapy) is a recommended treatment option with a quicker onset of action and improved outcomes compared with NB-UVB therapy alone.^32,33 Adverse events of coal tar include application-site irritation, folliculitis, contact dermatitis, phototoxicity, and skin pigmentation (Table 1).

Conclusion

Topical medications are versatile treatment options that can be utilized as monotherapy or adjunct therapy for mild to severe psoriasis. Benefits of topical agents include minimal required monitoring, few contraindications, and direct localized effect on plaques. Therefore, side effects with topical agent use rarely are systemic. Medication interactions are less of a concern with topical therapies; thus, they have better safety profiles compared with systemic therapies. This clinical review summarizes the recently published evidence-based guidelines from the AAD and NPF on the use of topical agents in psoriasis and may be a useful guiding framework for clinicians in their everyday practice.

Psoriasis is a chronic inflammatory skin disease characterized by erythematous scaly plaques that can invoke substantial pain, pruritus, and quality-of-life disturbance in patients. Topical therapies are the most commonly used medications for treating psoriasis, with one study (N = 128,308) showing that more than 85% of patients with psoriasis were managed solely with topical medications. ¹ For patients with mild to moderate psoriasis, topical agents alone may be able to control disease completely. For those with more severe disease, topical agents are used adjunctively with systemic or biologic agents to optimize disease control in localized areas.

The American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) published guidelines in 2020 for managing psoriasis with topical agents in adults.² This review presents the most up-to-date clinical recommendations for topical agent use in adult patients with psoriasis and elaborates on each drug’s pharmacologic and safety profile. Specifically, evidence-based treatment recommendations for topical steroids, calcineurin inhibitors (CNIs), vitamin D analogues, retinoids (tazarotene), emollients, keratolytics (salicylic acid), anthracenes (anthralin), and keratoplastics (coal tar) will be addressed (Table 1). Recommendations for combination therapy with other treatment modalities including UVB light therapy, biologics, and systemic nonbiologic agents also will be discussed.

Selecting a Topical Agent Based on Disease Localization

When treating patients with psoriasis with topical therapies, clinicians should take into consideration drug potency, as it determines how effective a treatment will be in penetrating the skin barrier. Plaque characteristics, such as distribution (localized vs widespread), anatomical localization (flexural, scalp, palms/soles/nails), size (large vs small), and thickness (thick vs thin), not only influence treatment effectiveness but also the incidence of drug-related adverse events. Furthermore, preferred topical therapies are tailored to each patient based on disease characteristics and activity. Coal tar and anthralin have been used less frequently than other topical therapies for psoriasis because of their undesirable side-effect profiles (Table 1).³

Face and Intertriginous Regions—The face and intertriginous areas are sensitive because skin tends to be thin in these regions. Emollients are recommended for disease in these locations given their safety and flexibility in use for most areas. Conversely, anthralin should be avoided on the face, intertriginous areas, and even highly visible locations because of the potential for skin staining. Low-potency corticosteroids also have utility in psoriasis distributed on the face and intertriginous regions. Additionally, application of steroids around the eyes should be cautioned because topical steroids can induce ocular complications such as glaucoma and cataracts in rare circumstances.⁴

Off-label use of CNIs for psoriasis on the face and intertriginous areas also is effective. Currently, there is a level B recommendation for off-label use of 0.1% tacrolimus for up to 8 weeks for inverse psoriasis or psoriasis on the face. Off-label use of pimecrolimus for 4 to 8 weeks also can be considered for inverse psoriasis. Combination therapy consisting of hydrocortisone with calcipotriol ointment is another effective regimen.⁵ One study also suggested that use of crisaborole for 4 to 8 weeks in intertriginous psoriasis can be effective and well tolerated.⁶

Scalp—The vehicle of medication administration is especially important in hair-bearing areas such as the scalp, as these areas are challenging for medication application and patient adherence. Thus, patient preferences for the vehicle must be considered. Several studies have been conducted to assess preference for various vehicles in scalp psoriasis. A foam or solution may be preferable to ointments, gels, or creams.⁷ Gels may be preferred over ointments.⁸ There is a level A recommendation supporting the use of class 1 to 7 topical steroids for a minimum of 4 weeks as initial and maintenance treatment of scalp psoriasis. The highest level of evidence (level A) also supports the use of calcipotriol foam or combination therapy of calcipotriol–betamethasone dipropionate gel for 4 to 12 weeks as treatment of mild to moderate scalp psoriasis.

Nails—Several options for topical medications have been recommended for the treatment of nail psoriasis. Currently, there is a level B recommendation for the use of tazarotene for the treatment of nail psoriasis. Another effective regimen is combination therapy with vitamin D analogues and betamethasone dipropionate.⁹ Topical steroid use for nail psoriasis should be limited to 12 weeks because of the risk for bone atrophy with chronic steroid use.

Palmoplantar—The palms and soles have a thicker epidermal layer than other areas of the body. As a result, class 1 corticosteroids can be used for palmoplantar psoriasis for more than 4 weeks with vigilant monitoring for adverse effects such as skin atrophy, tachyphylaxis, or tinea infection. Tazarotene also has been shown to be helpful in treating palmoplantar psoriasis.

Resistant Disease—Intralesional steroids are beneficial treatment options for recalcitrant psoriasis in glabrous areas, as well as for palmoplantar, nail, and scalp psoriasis. Up to 10 mg/mL of triamcinolone acetonide used every 3 to 4 weeks is an effective regimen.¹⁰Pregnancy/Breastfeeding—Women of childbearing potential have additional safety precautions that should be considered during medication selection. Emollients have been shown to be safe during pregnancy and lactation. Currently, there is little known about CNI use during pregnancy. During lactation, CNIs can be used by breastfeeding mothers in most areas, excluding the breasts. Evaluation of the safety of anthralin and vitamin D analogues during pregnancy and lactation have not been studied. For these agents, dermatologists need to use their clinical judgment to weigh the risks and benefits of medication, particularly in patients requiring occlusion, higher medication doses, or treatment over a large surface area. Salicylic acid should be used with caution in pregnant and breastfeeding mothers because it is a pregnancy category C drug. Lower-potency corticosteroids may be used with caution during pregnancy and breastfeeding. More potent corticosteroids and coal tar, however, should be avoided. Similarly, tazarotene use is contraindicated in pregnancy. According to the US Food and Drug Administration labels for all forms of topical tazarotene, a pregnancy test must be obtained 2 weeks prior to tazarotene treatment initiation in women of childbearing potential because of the risk for serious fetal malformations and toxicity.

Recommendations, Risks, and Benefits of Topical Therapy for the Management of Psoriasis

Topical Corticosteroids—Topical corticosteroids (TCs) are widely used for inflammatory skin conditions and are available in a variety of strengths (Table 2). They are thought to exert their action by regulating the gene transcription of proinflammatory mediators. For psoriasis, steroids are recommended for 2 to 4 weeks, depending on disease severity. Although potent and superpotent steroids are more effective than mild- to moderate-strength TCs, use of lower-potency TCs may be warranted depending on disease distribution and localization.¹¹ For treatment of psoriasis with no involvement of the intertriginous areas, use of class 1 to 5 TCs for up to 4 weeks is recommended.

For moderate to severe psoriasis with 20% or less body surface area (BSA) affected, combination therapy consisting of mometasone and salicylic acid has been shown to be more effective than mometasone alone.^12,13 There currently is a level A recommendation for the use of combination therapy with class 1 TCs and etanercept for 12 weeks in patients with moderate to severe psoriasis who require both systemic and topical therapies for disease control. Similarly, combination therapy with infliximab and high-potency TCs has a level B recommendation to enhance efficacy for the treatment of moderate to severe psoriasis.¹⁴ High-quality studies on the use of TCs with anti–IL-12/IL-23, anti–IL-23, and anti–IL-17 currently are unavailable, but the combination is not expected to be unsafe.^14,15 Combination therapy of betamethasone dipropionate ointment and low-dose cyclosporine is an alternative regimen with a level B recommendation.

The most common adverse effects with use of TCs are skin thinning and atrophy, telangiectasia, and striae (Table 1). With clinical improvement of disease, it is recommended that clinicians taper TCs to prevent rebound effect. To decrease TC-related adverse effects, clinicians should use combination therapy with steroid-sparing agents for disease maintenance, transition to lower-potency corticosteroids, or use intermittent steroid therapy. Systemic effects of TC use include hypothalamic-pituitary-adrenal axis suppression, Cushing syndrome, and osteonecrosis of the femoral head.^16-18 These systemic effects with TC use are rare unless treatment is for disease involving greater than 20% BSA or occlusion for more than 4 weeks.

Calcineurin Inhibitors—Calcineurin inhibitors inhibit calcineurin phosphorylation and T-cell activation, subsequently decreasing the expression of proinflammatory cytokines. Currently, they are not approved by the US Food and Drug Administration to treat psoriasis but have demonstrated efficacy in randomized control trials (RCTs) for facial and intertriginous psoriasis. In RCTs, 71% of patients using pimecrolimus cream 0.1% twice daily for 8 weeks achieved an investigator global assessment score of clear (0) or almost clear (1) compared with 21% of placebo-treated patients (N=57).¹⁹ Other trials have shown that 65% of patients receiving tacrolimus ointment 0.1% for 8 weeks achieved an investigator global assessment score of 0 or 1 compared with 31% of placebo-treated patients (N=167).²⁰ Because of their efficacy in RCTs, CNIs commonly are used off label to treat psoriasis.

The most common adverse effects with CNI use are burning, pruritus, and flushing with alcohol ingestion (Table 1). Additionally, CNIs have a black box warning that use may increase the risk for malignancy, but this risk has not been demonstrated with topical use in humans.²¹Vitamin D Analogues—The class of vitamin D analogues—calcipotriol/calcipotriene and calcitriol—frequently are used to treat psoriasis. Vitamin D analogues exert their beneficial effects by inhibiting keratinocyte proliferation and enhancing keratinocyte differentiation. They also are ideal for long-term use (up to 52 weeks) in mild to moderate psoriasis and can be used in combination with class 2 and 3 TCs. There is a level A recommendation that supports the use of combination therapy with calcipotriol and TCs for the treatment of mild to moderate psoriasis.

For severe psoriasis, many studies have investigated the efficacy of combination therapy with vitamin D analogues and systemic treatments. Combination therapy with calcipotriol and methotrexate or calcipotriol and acitretin are effective treatment regimens with level A recommendations. Calcipotriol–betamethasone dipropionate ointment in combination with low-dose cyclosporine is an alternative option with a level B recommendation. Because vitamin D analogues are inactivated by UVA and UVB radiation, clinicians should advise their patients to use vitamin D analogues after receiving UVB phototherapy.²²

Common adverse effects of vitamin D analogues include burning, pruritus, erythema, and dryness (Table 1). Hypercalcemia and parathyroid hormone suppression are extremely rare unless treatment occurs over a large surface area (>30% BSA) or the patient has concurrent renal disease or impairments in calcium metabolism.

Tazarotene—Tazarotene is a topical retinoid that acts by decreasing keratinocyte proliferation, facilitating keratinocyte differentiation, and inhibiting inflammation. Patients with mild to moderate psoriasis are recommended to receive tazarotene treatment for 8 to 12 weeks. In several RCTs, tazarotene gel 0.1% and tazarotene cream 0.1% and 0.05% achieved treatment success in treating plaque psoriasis.^23,24

For increased efficacy, clinicians can recommend combination therapy with tazarotene and a TC. Combination therapy with tazarotene and a mid- or high-potency TC for 8 to 16 weeks has been shown to be more effective than treatment with tazarotene alone.²⁵ Thus, there is a level A recommendation for use of this combination to treat mild to moderate psoriasis. Agents used in combination therapy work synergistically to decrease the length of treatment and increase the duration of remission. The frequency of adverse effects, such as irritation from tazarotene and skin atrophy from TCs, also are reduced.²⁶ Combination therapy with tazarotene and narrowband UVB (NB-UVB) is another effective option that requires less UV radiation than NB-UVB alone because of the synergistic effects of both treatment modalities.²⁷ Clinicians should counsel patients on the adverse effects of tazarotene, which include local irritation, burning, pruritus, and erythema (Table 1).

Emollients—Emollients are nonmedicated moisturizers that decrease the amount of transepidermal water loss. There is a level B recommendation for use of emollients and TCs in combination for 4 to 8 weeks to treat psoriasis. In fact, combination therapy with mometasone and emollients has demonstrated greater improvement in symptoms of palmoplantar psoriasis (ie, erythema, desquamation, infiltration, BSA involvement) than mometasone alone.²⁸ Emollients are safe options that can be used on all areas of the body and during pregnancy and lactation. Although adverse effects of emollients are rare, clinicians should counsel patients on the risk for contact dermatitis if specific allergies to ingredients/fragrances exist (Table 1).

Salicylic Acid—Salicylic acid is a topical keratolytic that can be used to treat psoriatic plaques. Use of salicylic acid for 8 to 16 weeks has been shown to be effective for mild to moderate psoriasis. Combination therapy of salicylic acid and TCs in patients with 20% or less BSA affected is a safe and effective option with a level B recommendation. Combination therapy with salicylic acid and calcipotriene, however, should be avoided because calcipotriene is inactivated by salicylic acid. It also is recommended that salicylic acid application follow phototherapy when both treatment modalities are used in combination.^29,30 Clinicians should be cautious about using salicylic acid in patients with renal or hepatic disease because of the increased risk for salicylate toxicity (Table 1).

Anthralin—Anthralin is a synthetic hydrocarbon derivative that has been shown to reduce inflammation and normalize keratinocyte proliferation through an unknown mechanism. It is recommended that patients with mild to moderate psoriasis receive anthralin treatment for 8 to 12 weeks, with a maximum application time of 2 hours per day. Combination therapy of excimer laser and anthralin has been shown to be more effective in treating psoriasis than anthralin alone.³¹ Therefore, clinicians have the option of including excimer laser therapy for additional disease control. Anthralin should be avoided on the face, flexural regions, and highly visible areas because of potential skin staining (Table 1). Other adverse effects include application-site burning and erythema.

Coal Tar—Coal tar is a heterogenous mixture of aromatic hydrocarbons that is an effective treatment of psoriasis because of its inherent anti-inflammatory and keratoplastic properties. There is high-quality evidence supporting a level A recommendation for coal tar use in mild to moderate psoriasis. Combination therapy with NB-UVB and coal tar (also known as Goeckerman therapy) is a recommended treatment option with a quicker onset of action and improved outcomes compared with NB-UVB therapy alone.^32,33 Adverse events of coal tar include application-site irritation, folliculitis, contact dermatitis, phototoxicity, and skin pigmentation (Table 1).

Conclusion

Topical medications are versatile treatment options that can be utilized as monotherapy or adjunct therapy for mild to severe psoriasis. Benefits of topical agents include minimal required monitoring, few contraindications, and direct localized effect on plaques. Therefore, side effects with topical agent use rarely are systemic. Medication interactions are less of a concern with topical therapies; thus, they have better safety profiles compared with systemic therapies. This clinical review summarizes the recently published evidence-based guidelines from the AAD and NPF on the use of topical agents in psoriasis and may be a useful guiding framework for clinicians in their everyday practice.

Psoriasis is a chronic inflammatory skin disease characterized by erythematous scaly plaques that can invoke substantial pain, pruritus, and quality-of-life disturbance in patients. Topical therapies are the most commonly used medications for treating psoriasis, with one study (N = 128,308) showing that more than 85% of patients with psoriasis were managed solely with topical medications. ¹ For patients with mild to moderate psoriasis, topical agents alone may be able to control disease completely. For those with more severe disease, topical agents are used adjunctively with systemic or biologic agents to optimize disease control in localized areas.

The American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) published guidelines in 2020 for managing psoriasis with topical agents in adults.² This review presents the most up-to-date clinical recommendations for topical agent use in adult patients with psoriasis and elaborates on each drug’s pharmacologic and safety profile. Specifically, evidence-based treatment recommendations for topical steroids, calcineurin inhibitors (CNIs), vitamin D analogues, retinoids (tazarotene), emollients, keratolytics (salicylic acid), anthracenes (anthralin), and keratoplastics (coal tar) will be addressed (Table 1). Recommendations for combination therapy with other treatment modalities including UVB light therapy, biologics, and systemic nonbiologic agents also will be discussed.

Selecting a Topical Agent Based on Disease Localization

When treating patients with psoriasis with topical therapies, clinicians should take into consideration drug potency, as it determines how effective a treatment will be in penetrating the skin barrier. Plaque characteristics, such as distribution (localized vs widespread), anatomical localization (flexural, scalp, palms/soles/nails), size (large vs small), and thickness (thick vs thin), not only influence treatment effectiveness but also the incidence of drug-related adverse events. Furthermore, preferred topical therapies are tailored to each patient based on disease characteristics and activity. Coal tar and anthralin have been used less frequently than other topical therapies for psoriasis because of their undesirable side-effect profiles (Table 1).³

Face and Intertriginous Regions—The face and intertriginous areas are sensitive because skin tends to be thin in these regions. Emollients are recommended for disease in these locations given their safety and flexibility in use for most areas. Conversely, anthralin should be avoided on the face, intertriginous areas, and even highly visible locations because of the potential for skin staining. Low-potency corticosteroids also have utility in psoriasis distributed on the face and intertriginous regions. Additionally, application of steroids around the eyes should be cautioned because topical steroids can induce ocular complications such as glaucoma and cataracts in rare circumstances.⁴

Off-label use of CNIs for psoriasis on the face and intertriginous areas also is effective. Currently, there is a level B recommendation for off-label use of 0.1% tacrolimus for up to 8 weeks for inverse psoriasis or psoriasis on the face. Off-label use of pimecrolimus for 4 to 8 weeks also can be considered for inverse psoriasis. Combination therapy consisting of hydrocortisone with calcipotriol ointment is another effective regimen.⁵ One study also suggested that use of crisaborole for 4 to 8 weeks in intertriginous psoriasis can be effective and well tolerated.⁶

Scalp—The vehicle of medication administration is especially important in hair-bearing areas such as the scalp, as these areas are challenging for medication application and patient adherence. Thus, patient preferences for the vehicle must be considered. Several studies have been conducted to assess preference for various vehicles in scalp psoriasis. A foam or solution may be preferable to ointments, gels, or creams.⁷ Gels may be preferred over ointments.⁸ There is a level A recommendation supporting the use of class 1 to 7 topical steroids for a minimum of 4 weeks as initial and maintenance treatment of scalp psoriasis. The highest level of evidence (level A) also supports the use of calcipotriol foam or combination therapy of calcipotriol–betamethasone dipropionate gel for 4 to 12 weeks as treatment of mild to moderate scalp psoriasis.

Nails—Several options for topical medications have been recommended for the treatment of nail psoriasis. Currently, there is a level B recommendation for the use of tazarotene for the treatment of nail psoriasis. Another effective regimen is combination therapy with vitamin D analogues and betamethasone dipropionate.⁹ Topical steroid use for nail psoriasis should be limited to 12 weeks because of the risk for bone atrophy with chronic steroid use.

Palmoplantar—The palms and soles have a thicker epidermal layer than other areas of the body. As a result, class 1 corticosteroids can be used for palmoplantar psoriasis for more than 4 weeks with vigilant monitoring for adverse effects such as skin atrophy, tachyphylaxis, or tinea infection. Tazarotene also has been shown to be helpful in treating palmoplantar psoriasis.

Resistant Disease—Intralesional steroids are beneficial treatment options for recalcitrant psoriasis in glabrous areas, as well as for palmoplantar, nail, and scalp psoriasis. Up to 10 mg/mL of triamcinolone acetonide used every 3 to 4 weeks is an effective regimen.¹⁰Pregnancy/Breastfeeding—Women of childbearing potential have additional safety precautions that should be considered during medication selection. Emollients have been shown to be safe during pregnancy and lactation. Currently, there is little known about CNI use during pregnancy. During lactation, CNIs can be used by breastfeeding mothers in most areas, excluding the breasts. Evaluation of the safety of anthralin and vitamin D analogues during pregnancy and lactation have not been studied. For these agents, dermatologists need to use their clinical judgment to weigh the risks and benefits of medication, particularly in patients requiring occlusion, higher medication doses, or treatment over a large surface area. Salicylic acid should be used with caution in pregnant and breastfeeding mothers because it is a pregnancy category C drug. Lower-potency corticosteroids may be used with caution during pregnancy and breastfeeding. More potent corticosteroids and coal tar, however, should be avoided. Similarly, tazarotene use is contraindicated in pregnancy. According to the US Food and Drug Administration labels for all forms of topical tazarotene, a pregnancy test must be obtained 2 weeks prior to tazarotene treatment initiation in women of childbearing potential because of the risk for serious fetal malformations and toxicity.

Recommendations, Risks, and Benefits of Topical Therapy for the Management of Psoriasis

Topical Corticosteroids—Topical corticosteroids (TCs) are widely used for inflammatory skin conditions and are available in a variety of strengths (Table 2). They are thought to exert their action by regulating the gene transcription of proinflammatory mediators. For psoriasis, steroids are recommended for 2 to 4 weeks, depending on disease severity. Although potent and superpotent steroids are more effective than mild- to moderate-strength TCs, use of lower-potency TCs may be warranted depending on disease distribution and localization.¹¹ For treatment of psoriasis with no involvement of the intertriginous areas, use of class 1 to 5 TCs for up to 4 weeks is recommended.

For moderate to severe psoriasis with 20% or less body surface area (BSA) affected, combination therapy consisting of mometasone and salicylic acid has been shown to be more effective than mometasone alone.^12,13 There currently is a level A recommendation for the use of combination therapy with class 1 TCs and etanercept for 12 weeks in patients with moderate to severe psoriasis who require both systemic and topical therapies for disease control. Similarly, combination therapy with infliximab and high-potency TCs has a level B recommendation to enhance efficacy for the treatment of moderate to severe psoriasis.¹⁴ High-quality studies on the use of TCs with anti–IL-12/IL-23, anti–IL-23, and anti–IL-17 currently are unavailable, but the combination is not expected to be unsafe.^14,15 Combination therapy of betamethasone dipropionate ointment and low-dose cyclosporine is an alternative regimen with a level B recommendation.

The most common adverse effects with use of TCs are skin thinning and atrophy, telangiectasia, and striae (Table 1). With clinical improvement of disease, it is recommended that clinicians taper TCs to prevent rebound effect. To decrease TC-related adverse effects, clinicians should use combination therapy with steroid-sparing agents for disease maintenance, transition to lower-potency corticosteroids, or use intermittent steroid therapy. Systemic effects of TC use include hypothalamic-pituitary-adrenal axis suppression, Cushing syndrome, and osteonecrosis of the femoral head.^16-18 These systemic effects with TC use are rare unless treatment is for disease involving greater than 20% BSA or occlusion for more than 4 weeks.

Calcineurin Inhibitors—Calcineurin inhibitors inhibit calcineurin phosphorylation and T-cell activation, subsequently decreasing the expression of proinflammatory cytokines. Currently, they are not approved by the US Food and Drug Administration to treat psoriasis but have demonstrated efficacy in randomized control trials (RCTs) for facial and intertriginous psoriasis. In RCTs, 71% of patients using pimecrolimus cream 0.1% twice daily for 8 weeks achieved an investigator global assessment score of clear (0) or almost clear (1) compared with 21% of placebo-treated patients (N=57).¹⁹ Other trials have shown that 65% of patients receiving tacrolimus ointment 0.1% for 8 weeks achieved an investigator global assessment score of 0 or 1 compared with 31% of placebo-treated patients (N=167).²⁰ Because of their efficacy in RCTs, CNIs commonly are used off label to treat psoriasis.

The most common adverse effects with CNI use are burning, pruritus, and flushing with alcohol ingestion (Table 1). Additionally, CNIs have a black box warning that use may increase the risk for malignancy, but this risk has not been demonstrated with topical use in humans.²¹Vitamin D Analogues—The class of vitamin D analogues—calcipotriol/calcipotriene and calcitriol—frequently are used to treat psoriasis. Vitamin D analogues exert their beneficial effects by inhibiting keratinocyte proliferation and enhancing keratinocyte differentiation. They also are ideal for long-term use (up to 52 weeks) in mild to moderate psoriasis and can be used in combination with class 2 and 3 TCs. There is a level A recommendation that supports the use of combination therapy with calcipotriol and TCs for the treatment of mild to moderate psoriasis.

For severe psoriasis, many studies have investigated the efficacy of combination therapy with vitamin D analogues and systemic treatments. Combination therapy with calcipotriol and methotrexate or calcipotriol and acitretin are effective treatment regimens with level A recommendations. Calcipotriol–betamethasone dipropionate ointment in combination with low-dose cyclosporine is an alternative option with a level B recommendation. Because vitamin D analogues are inactivated by UVA and UVB radiation, clinicians should advise their patients to use vitamin D analogues after receiving UVB phototherapy.²²

Common adverse effects of vitamin D analogues include burning, pruritus, erythema, and dryness (Table 1). Hypercalcemia and parathyroid hormone suppression are extremely rare unless treatment occurs over a large surface area (>30% BSA) or the patient has concurrent renal disease or impairments in calcium metabolism.

Tazarotene—Tazarotene is a topical retinoid that acts by decreasing keratinocyte proliferation, facilitating keratinocyte differentiation, and inhibiting inflammation. Patients with mild to moderate psoriasis are recommended to receive tazarotene treatment for 8 to 12 weeks. In several RCTs, tazarotene gel 0.1% and tazarotene cream 0.1% and 0.05% achieved treatment success in treating plaque psoriasis.^23,24

For increased efficacy, clinicians can recommend combination therapy with tazarotene and a TC. Combination therapy with tazarotene and a mid- or high-potency TC for 8 to 16 weeks has been shown to be more effective than treatment with tazarotene alone.²⁵ Thus, there is a level A recommendation for use of this combination to treat mild to moderate psoriasis. Agents used in combination therapy work synergistically to decrease the length of treatment and increase the duration of remission. The frequency of adverse effects, such as irritation from tazarotene and skin atrophy from TCs, also are reduced.²⁶ Combination therapy with tazarotene and narrowband UVB (NB-UVB) is another effective option that requires less UV radiation than NB-UVB alone because of the synergistic effects of both treatment modalities.²⁷ Clinicians should counsel patients on the adverse effects of tazarotene, which include local irritation, burning, pruritus, and erythema (Table 1).

Emollients—Emollients are nonmedicated moisturizers that decrease the amount of transepidermal water loss. There is a level B recommendation for use of emollients and TCs in combination for 4 to 8 weeks to treat psoriasis. In fact, combination therapy with mometasone and emollients has demonstrated greater improvement in symptoms of palmoplantar psoriasis (ie, erythema, desquamation, infiltration, BSA involvement) than mometasone alone.²⁸ Emollients are safe options that can be used on all areas of the body and during pregnancy and lactation. Although adverse effects of emollients are rare, clinicians should counsel patients on the risk for contact dermatitis if specific allergies to ingredients/fragrances exist (Table 1).

Salicylic Acid—Salicylic acid is a topical keratolytic that can be used to treat psoriatic plaques. Use of salicylic acid for 8 to 16 weeks has been shown to be effective for mild to moderate psoriasis. Combination therapy of salicylic acid and TCs in patients with 20% or less BSA affected is a safe and effective option with a level B recommendation. Combination therapy with salicylic acid and calcipotriene, however, should be avoided because calcipotriene is inactivated by salicylic acid. It also is recommended that salicylic acid application follow phototherapy when both treatment modalities are used in combination.^29,30 Clinicians should be cautious about using salicylic acid in patients with renal or hepatic disease because of the increased risk for salicylate toxicity (Table 1).

Anthralin—Anthralin is a synthetic hydrocarbon derivative that has been shown to reduce inflammation and normalize keratinocyte proliferation through an unknown mechanism. It is recommended that patients with mild to moderate psoriasis receive anthralin treatment for 8 to 12 weeks, with a maximum application time of 2 hours per day. Combination therapy of excimer laser and anthralin has been shown to be more effective in treating psoriasis than anthralin alone.³¹ Therefore, clinicians have the option of including excimer laser therapy for additional disease control. Anthralin should be avoided on the face, flexural regions, and highly visible areas because of potential skin staining (Table 1). Other adverse effects include application-site burning and erythema.

Coal Tar—Coal tar is a heterogenous mixture of aromatic hydrocarbons that is an effective treatment of psoriasis because of its inherent anti-inflammatory and keratoplastic properties. There is high-quality evidence supporting a level A recommendation for coal tar use in mild to moderate psoriasis. Combination therapy with NB-UVB and coal tar (also known as Goeckerman therapy) is a recommended treatment option with a quicker onset of action and improved outcomes compared with NB-UVB therapy alone.^32,33 Adverse events of coal tar include application-site irritation, folliculitis, contact dermatitis, phototoxicity, and skin pigmentation (Table 1).

Conclusion

Topical medications are versatile treatment options that can be utilized as monotherapy or adjunct therapy for mild to severe psoriasis. Benefits of topical agents include minimal required monitoring, few contraindications, and direct localized effect on plaques. Therefore, side effects with topical agent use rarely are systemic. Medication interactions are less of a concern with topical therapies; thus, they have better safety profiles compared with systemic therapies. This clinical review summarizes the recently published evidence-based guidelines from the AAD and NPF on the use of topical agents in psoriasis and may be a useful guiding framework for clinicians in their everyday practice.

Atopic dermatitis (AD) is a chronic inflammatory skin disorder affecting 7% of adults and 13% of children in the United States.^1,2 Atopic dermatitis is characterized by pruritus, dry skin, and pain, all of which can negatively impact quality of life and put patients at higher risk for psychiatric comorbidities such as anxiety and depression.³ The pathogenesis of AD is multifactorial, involving genetics, epidermal barrier dysfunction, and immune dysregulation. Overactivation of helper T cell (T_H2) pathway cytokines, including IL-4, IL-13, and IL-31, is thought to propagate both inflammation and pruritus, which are central to AD. The JAK-STAT signaling pathway plays a pivotal role in the immune system dysregulation and exaggeration of T_H2 cell response, making JAK-STAT inhibitors (or JAK inhibitors) strong theoretical candidates for the treatment of AD.⁴ In humans, the Janus kinases are composed of 4 different members—JAK1, JAK2, JAK3, and tyrosine kinase 2—all of which can be targeted by JAK inhibitors.⁵

JAK inhibitors such as tofacitinib have already been approved by the US Food and Drug Administration (FDA) to treat various inflammatory conditions, including rheumatoid arthritis, ulcerative colitis, and psoriatic arthritis; other JAK inhibitors such as baricitinib are only approved for patients with rheumatoid arthritis.^6,7 The success of these small molecule inhibitors in these immune-mediated conditions make them attractive candidates for the treatment of AD. Several JAK inhibitors are in phase 2 and phase 3 clinical trials as oral therapies (moderate to severe AD) or as topical treatments (mild to moderate AD). Currently, ruxolitinib (RUX) is the only topical JAK inhibitor that is FDA approved for the treatment of AD in the United States.⁸ In this editorial, we focus on recent trials of JAK inhibitors tested in patients with AD, including topical RUX, as well as oral abrocitinib, upadacitinib, and baricitinib.

Topical RUX in AD

Ruxolitinib is a topical JAK1/2 small molecule inhibitor approved by the FDA for the treatment of AD in 2021. In a randomized trial by Kim et al⁹ in 2020, all tested regimens of RUX demonstrated significant improvement in eczema area and severity index (EASI) scores vs vehicle; notably, RUX cream 1.5% applied twice daily achieved the greatest mean percentage change in baseline EASI score vs vehicle at 4 weeks (76.1% vs 15.5%; P<.0001). Ruxolitinib cream was well tolerated through week 8 of the trial, and all adverse events (AEs) were mild to moderate in severity and comparable to those in the vehicle group.⁹

Topical JAK inhibitors appear to be effective for mild to moderate AD and have had an acceptable safety profile in clinical trials thus far. Although topical corticosteroids and calcineurin inhibitors can have great clinical benefit in AD, they are recommended for short-term use given side effects such as thinning of the skin, burning, or telangiectasia formation.^10,11 The hope is that topical JAK inhibitors may be an alternative to standard topical treatments for AD, as they can be used for longer periods due to a safer side-effect profile.

Oral JAK Inhibitors in AD

Several oral JAK inhibitors are undergoing investigation for the systemic treatment of moderate to severe AD. Abrocitinib is an oral JAK1 inhibitor that has demonstrated efficacy in several phase 3 trials in patients with moderate to severe AD. In a 2021 trial, patients were randomized in a 2:2:2:1 ratio to receive abrocitinib 200 mg daily, abrocitinib 100 mg daily, subcutaneous dupilumab 300 mg every other week, or placebo, respectively.¹² Patients in both abrocitinib groups showed significant improvement in AD vs placebo, and EASI-75 response was achieved in 70.3%, 58.7%, 58.1%, and 27.1% of patients, respectively (P<.001 for both abrocitinib doses vs placebo). Adverse events occurred more frequently in the abrocitinib 200-mg group vs placebo. Nausea, acne, nasopharyngitis, and headache were the most frequently reported AEs with abrocitinib.¹² Another phase 3 trial by Silverberg et al¹³ (N=391) had similar treatment results, with 38.1% of participants receiving abrocitinib 200 mg and 28.4% of participants receiving abrocitinib 100 mg achieving investigator global assessment scores of 0 (clear) or 1 (almost clear) vs 9.1% of participants receiving placebo (P<.001). Abrocitinib was well tolerated in this trial with few serious AEs (ie, herpangina [0.6%], pneumonia [0.6%]).¹³ In both trials, there were rare instances of laboratory values indicating thrombocytopenia with the 200-mg dose (0.9%¹² and 3.2%¹³) without any clinical manifestations. Although a decrease in platelets was observed, no thrombocytopenia occurred in the abrocitinib 100-mg group in the latter trial.¹³

Baricitinib is another oral inhibitor of JAK1 and JAK2 with potential for the treatment of AD. One randomized trial (N=329) demonstrated its efficacy in combination with a topical corticosteroid (TCS). At 16 weeks, a higher number of participants treated with baricitinib and TCS achieved investigator global assessment scores of 0 (clear) or 1 (almost clear) compared to those who received placebo and TCS (31% with baricitinib 4 mg + TCS, 24% with baricitinib 2 mg + TCS, and 15% with placebo + TCS).¹⁴ Similarly, in BREEZE-AD5,another phase 3 trial (N=440), baricitinib monotherapy demonstrated a higher rate of treatment success vs placebo.¹⁵ Specifically, 13% of patients treated with baricitinib 1 mg and 30% of those treated with baricitinib 2 mg achieved 75% or greater reduction in EASI scores compared to 8% in the placebo group. The most common AEs associated with baricitinib were nasopharyngitis and headache. Adverse events occurred with similar frequency across both experimental and control groups.¹⁵ Reich et al¹⁴ demonstrated a higher overall rate of AEs—most commonly nasopharyngitis, upper respiratory tract infections, and folliculitis—in baricitinib-treated patients; however, serious AEs occurred with similar frequency across all groups, including the control group.

The selective JAK1 inhibitor upadacitinib also is undergoing testing in treating moderate to severe AD. In one trial, 167 patients were randomized to once daily oral upadacitinib 7.5 mg, 15 mg, or 30 mg or placebo.¹⁶ All doses of upadacitinib demonstrated considerably higher percentage improvements from baseline in EASI scores compared to placebo at 16 weeks with a clear dose-response relationship (39%, 62%, and 74% vs 23%, respectively). In this trial, there were no dose-limiting safety events. Serious AEs were infrequent, occurring in 4.8%, 2.4%, and 0% of upadacitinib groups vs 2.5% for placebo. The serious AEs observed with upadacitinib were 1 case of appendicitis, lower jaw pericoronitis in a patient with a history of repeated tooth infections, and an exacerbation of AD.¹⁶

Tofacitinib, another JAK inhibitor, has been shown to increase the risk for blood clots and death in a large trial in the treatment of rheumatoid arthritis. Following this study, the FDA is requiring black box warnings for tofacitinib and also for the 2 JAK inhibitors baricitinib and upadacitinib regarding the risks for heart-related events, cancer, blood clots, and death. Given that these medications share a similar mechanism of action to tofacitinib, they may have similar risks, though they have not yet been fully evaluated in large safety trials.¹⁷

With more recent investigation into novel therapeutics for AD, oral JAK inhibitors may play an important role in the future to treat patients with moderate to severe AD with inadequate response or contraindications to other systemic therapies. In trials thus far, oral JAK inhibitors have exhibited acceptable safety profiles and have demonstrated treatment success in AD. More randomized, controlled, phase 3 studies with larger patient populations are required to confirm their potential as effective treatments and elucidate their long-term safety.

Deucravacitinib in Psoriasis

Deucravacitinib is a first-in-class, oral, selective TYK2 inhibitor currently undergoing testing for the treatment of psoriasis. A randomized phase 2 trial (N=267) found that deucravacitinib was more effective than placebo in treating chronic plaque psoriasis at doses of 3 to 12 mg daily.¹⁸ The percentage of participants with a 75% or greater reduction from baseline in the psoriasis area and severity index score was 7% with placebo, 9% with deucravacitinib 3 mg every other day (P=.49 vs placebo), 39% with 3 mg once daily (P<.001 vs placebo), 69% with 3 mg twice daily (P<.001 vs placebo), 67% with 6 mg twice daily (P<.001 vs placebo), and 75% with 12 mg once daily (P<.001 vs placebo). The most commonly reported AEs were nasopharyngitis, headache, diarrhea, nausea, and upper respiratory tract infection. Adverse events occurred in 51% of participants in the control group and in 55% to 80% of those in the experimental groups. Additionally, there was 1 reported case of melanoma (stage 0) 96 days after the start of treatment in a patient in the 3-mg once-daily group. Serious AEs occurred in only 0% to 2% of participants who received deucravacitinib.¹⁸

Two phase 3 trials—POETYK PSO-1 and POETYK PSO-2 (N=1686)—found deucravacitinib to be notably more effective than both placebo and apremilast in treating psoriasis.¹⁹ Among participants receiving deucravacitinib 6 mg daily, 58.7% and 53.6% in the 2 respective trials achieved psoriasis area and severity index 75 response vs 12.7% and 9.4% receiving placebo and 35.1% and 40.2% receiving apremilast. Overall, the treatment was well tolerated, with a low rate of discontinuation of deucravacitinib due to AEs (2.4% of patients on deucravacitinib compared to 3.8% on placebo and 5.2% on apremilast). The most frequently observed AEs with deucravacitinib were nasopharyngitis and upper respiratory tract infection. The full results of these trials are expected to be published soon.^19,20

Final Thoughts

Overall, JAK inhibitors are a novel class of therapeutics that may have further success in the treatment of other dermatologic conditions that negatively affect patients’ quality of life and productivity. We should look forward to additional successful trials with these promising medications.

Atopic dermatitis (AD) is a chronic inflammatory skin disorder affecting 7% of adults and 13% of children in the United States.^1,2 Atopic dermatitis is characterized by pruritus, dry skin, and pain, all of which can negatively impact quality of life and put patients at higher risk for psychiatric comorbidities such as anxiety and depression.³ The pathogenesis of AD is multifactorial, involving genetics, epidermal barrier dysfunction, and immune dysregulation. Overactivation of helper T cell (T_H2) pathway cytokines, including IL-4, IL-13, and IL-31, is thought to propagate both inflammation and pruritus, which are central to AD. The JAK-STAT signaling pathway plays a pivotal role in the immune system dysregulation and exaggeration of T_H2 cell response, making JAK-STAT inhibitors (or JAK inhibitors) strong theoretical candidates for the treatment of AD.⁴ In humans, the Janus kinases are composed of 4 different members—JAK1, JAK2, JAK3, and tyrosine kinase 2—all of which can be targeted by JAK inhibitors.⁵

JAK inhibitors such as tofacitinib have already been approved by the US Food and Drug Administration (FDA) to treat various inflammatory conditions, including rheumatoid arthritis, ulcerative colitis, and psoriatic arthritis; other JAK inhibitors such as baricitinib are only approved for patients with rheumatoid arthritis.^6,7 The success of these small molecule inhibitors in these immune-mediated conditions make them attractive candidates for the treatment of AD. Several JAK inhibitors are in phase 2 and phase 3 clinical trials as oral therapies (moderate to severe AD) or as topical treatments (mild to moderate AD). Currently, ruxolitinib (RUX) is the only topical JAK inhibitor that is FDA approved for the treatment of AD in the United States.⁸ In this editorial, we focus on recent trials of JAK inhibitors tested in patients with AD, including topical RUX, as well as oral abrocitinib, upadacitinib, and baricitinib.

Topical RUX in AD

Ruxolitinib is a topical JAK1/2 small molecule inhibitor approved by the FDA for the treatment of AD in 2021. In a randomized trial by Kim et al⁹ in 2020, all tested regimens of RUX demonstrated significant improvement in eczema area and severity index (EASI) scores vs vehicle; notably, RUX cream 1.5% applied twice daily achieved the greatest mean percentage change in baseline EASI score vs vehicle at 4 weeks (76.1% vs 15.5%; P<.0001). Ruxolitinib cream was well tolerated through week 8 of the trial, and all adverse events (AEs) were mild to moderate in severity and comparable to those in the vehicle group.⁹

Topical JAK inhibitors appear to be effective for mild to moderate AD and have had an acceptable safety profile in clinical trials thus far. Although topical corticosteroids and calcineurin inhibitors can have great clinical benefit in AD, they are recommended for short-term use given side effects such as thinning of the skin, burning, or telangiectasia formation.^10,11 The hope is that topical JAK inhibitors may be an alternative to standard topical treatments for AD, as they can be used for longer periods due to a safer side-effect profile.

Oral JAK Inhibitors in AD

Several oral JAK inhibitors are undergoing investigation for the systemic treatment of moderate to severe AD. Abrocitinib is an oral JAK1 inhibitor that has demonstrated efficacy in several phase 3 trials in patients with moderate to severe AD. In a 2021 trial, patients were randomized in a 2:2:2:1 ratio to receive abrocitinib 200 mg daily, abrocitinib 100 mg daily, subcutaneous dupilumab 300 mg every other week, or placebo, respectively.¹² Patients in both abrocitinib groups showed significant improvement in AD vs placebo, and EASI-75 response was achieved in 70.3%, 58.7%, 58.1%, and 27.1% of patients, respectively (P<.001 for both abrocitinib doses vs placebo). Adverse events occurred more frequently in the abrocitinib 200-mg group vs placebo. Nausea, acne, nasopharyngitis, and headache were the most frequently reported AEs with abrocitinib.¹² Another phase 3 trial by Silverberg et al¹³ (N=391) had similar treatment results, with 38.1% of participants receiving abrocitinib 200 mg and 28.4% of participants receiving abrocitinib 100 mg achieving investigator global assessment scores of 0 (clear) or 1 (almost clear) vs 9.1% of participants receiving placebo (P<.001). Abrocitinib was well tolerated in this trial with few serious AEs (ie, herpangina [0.6%], pneumonia [0.6%]).¹³ In both trials, there were rare instances of laboratory values indicating thrombocytopenia with the 200-mg dose (0.9%¹² and 3.2%¹³) without any clinical manifestations. Although a decrease in platelets was observed, no thrombocytopenia occurred in the abrocitinib 100-mg group in the latter trial.¹³

Baricitinib is another oral inhibitor of JAK1 and JAK2 with potential for the treatment of AD. One randomized trial (N=329) demonstrated its efficacy in combination with a topical corticosteroid (TCS). At 16 weeks, a higher number of participants treated with baricitinib and TCS achieved investigator global assessment scores of 0 (clear) or 1 (almost clear) compared to those who received placebo and TCS (31% with baricitinib 4 mg + TCS, 24% with baricitinib 2 mg + TCS, and 15% with placebo + TCS).¹⁴ Similarly, in BREEZE-AD5,another phase 3 trial (N=440), baricitinib monotherapy demonstrated a higher rate of treatment success vs placebo.¹⁵ Specifically, 13% of patients treated with baricitinib 1 mg and 30% of those treated with baricitinib 2 mg achieved 75% or greater reduction in EASI scores compared to 8% in the placebo group. The most common AEs associated with baricitinib were nasopharyngitis and headache. Adverse events occurred with similar frequency across both experimental and control groups.¹⁵ Reich et al¹⁴ demonstrated a higher overall rate of AEs—most commonly nasopharyngitis, upper respiratory tract infections, and folliculitis—in baricitinib-treated patients; however, serious AEs occurred with similar frequency across all groups, including the control group.

The selective JAK1 inhibitor upadacitinib also is undergoing testing in treating moderate to severe AD. In one trial, 167 patients were randomized to once daily oral upadacitinib 7.5 mg, 15 mg, or 30 mg or placebo.¹⁶ All doses of upadacitinib demonstrated considerably higher percentage improvements from baseline in EASI scores compared to placebo at 16 weeks with a clear dose-response relationship (39%, 62%, and 74% vs 23%, respectively). In this trial, there were no dose-limiting safety events. Serious AEs were infrequent, occurring in 4.8%, 2.4%, and 0% of upadacitinib groups vs 2.5% for placebo. The serious AEs observed with upadacitinib were 1 case of appendicitis, lower jaw pericoronitis in a patient with a history of repeated tooth infections, and an exacerbation of AD.¹⁶

Tofacitinib, another JAK inhibitor, has been shown to increase the risk for blood clots and death in a large trial in the treatment of rheumatoid arthritis. Following this study, the FDA is requiring black box warnings for tofacitinib and also for the 2 JAK inhibitors baricitinib and upadacitinib regarding the risks for heart-related events, cancer, blood clots, and death. Given that these medications share a similar mechanism of action to tofacitinib, they may have similar risks, though they have not yet been fully evaluated in large safety trials.¹⁷

With more recent investigation into novel therapeutics for AD, oral JAK inhibitors may play an important role in the future to treat patients with moderate to severe AD with inadequate response or contraindications to other systemic therapies. In trials thus far, oral JAK inhibitors have exhibited acceptable safety profiles and have demonstrated treatment success in AD. More randomized, controlled, phase 3 studies with larger patient populations are required to confirm their potential as effective treatments and elucidate their long-term safety.

Deucravacitinib in Psoriasis

Deucravacitinib is a first-in-class, oral, selective TYK2 inhibitor currently undergoing testing for the treatment of psoriasis. A randomized phase 2 trial (N=267) found that deucravacitinib was more effective than placebo in treating chronic plaque psoriasis at doses of 3 to 12 mg daily.¹⁸ The percentage of participants with a 75% or greater reduction from baseline in the psoriasis area and severity index score was 7% with placebo, 9% with deucravacitinib 3 mg every other day (P=.49 vs placebo), 39% with 3 mg once daily (P<.001 vs placebo), 69% with 3 mg twice daily (P<.001 vs placebo), 67% with 6 mg twice daily (P<.001 vs placebo), and 75% with 12 mg once daily (P<.001 vs placebo). The most commonly reported AEs were nasopharyngitis, headache, diarrhea, nausea, and upper respiratory tract infection. Adverse events occurred in 51% of participants in the control group and in 55% to 80% of those in the experimental groups. Additionally, there was 1 reported case of melanoma (stage 0) 96 days after the start of treatment in a patient in the 3-mg once-daily group. Serious AEs occurred in only 0% to 2% of participants who received deucravacitinib.¹⁸

Two phase 3 trials—POETYK PSO-1 and POETYK PSO-2 (N=1686)—found deucravacitinib to be notably more effective than both placebo and apremilast in treating psoriasis.¹⁹ Among participants receiving deucravacitinib 6 mg daily, 58.7% and 53.6% in the 2 respective trials achieved psoriasis area and severity index 75 response vs 12.7% and 9.4% receiving placebo and 35.1% and 40.2% receiving apremilast. Overall, the treatment was well tolerated, with a low rate of discontinuation of deucravacitinib due to AEs (2.4% of patients on deucravacitinib compared to 3.8% on placebo and 5.2% on apremilast). The most frequently observed AEs with deucravacitinib were nasopharyngitis and upper respiratory tract infection. The full results of these trials are expected to be published soon.^19,20

Final Thoughts

Overall, JAK inhibitors are a novel class of therapeutics that may have further success in the treatment of other dermatologic conditions that negatively affect patients’ quality of life and productivity. We should look forward to additional successful trials with these promising medications.

Atopic dermatitis (AD) is a chronic inflammatory skin disorder affecting 7% of adults and 13% of children in the United States.^1,2 Atopic dermatitis is characterized by pruritus, dry skin, and pain, all of which can negatively impact quality of life and put patients at higher risk for psychiatric comorbidities such as anxiety and depression.³ The pathogenesis of AD is multifactorial, involving genetics, epidermal barrier dysfunction, and immune dysregulation. Overactivation of helper T cell (T_H2) pathway cytokines, including IL-4, IL-13, and IL-31, is thought to propagate both inflammation and pruritus, which are central to AD. The JAK-STAT signaling pathway plays a pivotal role in the immune system dysregulation and exaggeration of T_H2 cell response, making JAK-STAT inhibitors (or JAK inhibitors) strong theoretical candidates for the treatment of AD.⁴ In humans, the Janus kinases are composed of 4 different members—JAK1, JAK2, JAK3, and tyrosine kinase 2—all of which can be targeted by JAK inhibitors.⁵

JAK inhibitors such as tofacitinib have already been approved by the US Food and Drug Administration (FDA) to treat various inflammatory conditions, including rheumatoid arthritis, ulcerative colitis, and psoriatic arthritis; other JAK inhibitors such as baricitinib are only approved for patients with rheumatoid arthritis.^6,7 The success of these small molecule inhibitors in these immune-mediated conditions make them attractive candidates for the treatment of AD. Several JAK inhibitors are in phase 2 and phase 3 clinical trials as oral therapies (moderate to severe AD) or as topical treatments (mild to moderate AD). Currently, ruxolitinib (RUX) is the only topical JAK inhibitor that is FDA approved for the treatment of AD in the United States.⁸ In this editorial, we focus on recent trials of JAK inhibitors tested in patients with AD, including topical RUX, as well as oral abrocitinib, upadacitinib, and baricitinib.

Topical RUX in AD

Ruxolitinib is a topical JAK1/2 small molecule inhibitor approved by the FDA for the treatment of AD in 2021. In a randomized trial by Kim et al⁹ in 2020, all tested regimens of RUX demonstrated significant improvement in eczema area and severity index (EASI) scores vs vehicle; notably, RUX cream 1.5% applied twice daily achieved the greatest mean percentage change in baseline EASI score vs vehicle at 4 weeks (76.1% vs 15.5%; P<.0001). Ruxolitinib cream was well tolerated through week 8 of the trial, and all adverse events (AEs) were mild to moderate in severity and comparable to those in the vehicle group.⁹

Topical JAK inhibitors appear to be effective for mild to moderate AD and have had an acceptable safety profile in clinical trials thus far. Although topical corticosteroids and calcineurin inhibitors can have great clinical benefit in AD, they are recommended for short-term use given side effects such as thinning of the skin, burning, or telangiectasia formation.^10,11 The hope is that topical JAK inhibitors may be an alternative to standard topical treatments for AD, as they can be used for longer periods due to a safer side-effect profile.

Oral JAK Inhibitors in AD

Several oral JAK inhibitors are undergoing investigation for the systemic treatment of moderate to severe AD. Abrocitinib is an oral JAK1 inhibitor that has demonstrated efficacy in several phase 3 trials in patients with moderate to severe AD. In a 2021 trial, patients were randomized in a 2:2:2:1 ratio to receive abrocitinib 200 mg daily, abrocitinib 100 mg daily, subcutaneous dupilumab 300 mg every other week, or placebo, respectively.¹² Patients in both abrocitinib groups showed significant improvement in AD vs placebo, and EASI-75 response was achieved in 70.3%, 58.7%, 58.1%, and 27.1% of patients, respectively (P<.001 for both abrocitinib doses vs placebo). Adverse events occurred more frequently in the abrocitinib 200-mg group vs placebo. Nausea, acne, nasopharyngitis, and headache were the most frequently reported AEs with abrocitinib.¹² Another phase 3 trial by Silverberg et al¹³ (N=391) had similar treatment results, with 38.1% of participants receiving abrocitinib 200 mg and 28.4% of participants receiving abrocitinib 100 mg achieving investigator global assessment scores of 0 (clear) or 1 (almost clear) vs 9.1% of participants receiving placebo (P<.001). Abrocitinib was well tolerated in this trial with few serious AEs (ie, herpangina [0.6%], pneumonia [0.6%]).¹³ In both trials, there were rare instances of laboratory values indicating thrombocytopenia with the 200-mg dose (0.9%¹² and 3.2%¹³) without any clinical manifestations. Although a decrease in platelets was observed, no thrombocytopenia occurred in the abrocitinib 100-mg group in the latter trial.¹³

Baricitinib is another oral inhibitor of JAK1 and JAK2 with potential for the treatment of AD. One randomized trial (N=329) demonstrated its efficacy in combination with a topical corticosteroid (TCS). At 16 weeks, a higher number of participants treated with baricitinib and TCS achieved investigator global assessment scores of 0 (clear) or 1 (almost clear) compared to those who received placebo and TCS (31% with baricitinib 4 mg + TCS, 24% with baricitinib 2 mg + TCS, and 15% with placebo + TCS).¹⁴ Similarly, in BREEZE-AD5,another phase 3 trial (N=440), baricitinib monotherapy demonstrated a higher rate of treatment success vs placebo.¹⁵ Specifically, 13% of patients treated with baricitinib 1 mg and 30% of those treated with baricitinib 2 mg achieved 75% or greater reduction in EASI scores compared to 8% in the placebo group. The most common AEs associated with baricitinib were nasopharyngitis and headache. Adverse events occurred with similar frequency across both experimental and control groups.¹⁵ Reich et al¹⁴ demonstrated a higher overall rate of AEs—most commonly nasopharyngitis, upper respiratory tract infections, and folliculitis—in baricitinib-treated patients; however, serious AEs occurred with similar frequency across all groups, including the control group.

The selective JAK1 inhibitor upadacitinib also is undergoing testing in treating moderate to severe AD. In one trial, 167 patients were randomized to once daily oral upadacitinib 7.5 mg, 15 mg, or 30 mg or placebo.¹⁶ All doses of upadacitinib demonstrated considerably higher percentage improvements from baseline in EASI scores compared to placebo at 16 weeks with a clear dose-response relationship (39%, 62%, and 74% vs 23%, respectively). In this trial, there were no dose-limiting safety events. Serious AEs were infrequent, occurring in 4.8%, 2.4%, and 0% of upadacitinib groups vs 2.5% for placebo. The serious AEs observed with upadacitinib were 1 case of appendicitis, lower jaw pericoronitis in a patient with a history of repeated tooth infections, and an exacerbation of AD.¹⁶

Tofacitinib, another JAK inhibitor, has been shown to increase the risk for blood clots and death in a large trial in the treatment of rheumatoid arthritis. Following this study, the FDA is requiring black box warnings for tofacitinib and also for the 2 JAK inhibitors baricitinib and upadacitinib regarding the risks for heart-related events, cancer, blood clots, and death. Given that these medications share a similar mechanism of action to tofacitinib, they may have similar risks, though they have not yet been fully evaluated in large safety trials.¹⁷

With more recent investigation into novel therapeutics for AD, oral JAK inhibitors may play an important role in the future to treat patients with moderate to severe AD with inadequate response or contraindications to other systemic therapies. In trials thus far, oral JAK inhibitors have exhibited acceptable safety profiles and have demonstrated treatment success in AD. More randomized, controlled, phase 3 studies with larger patient populations are required to confirm their potential as effective treatments and elucidate their long-term safety.

Deucravacitinib in Psoriasis

Deucravacitinib is a first-in-class, oral, selective TYK2 inhibitor currently undergoing testing for the treatment of psoriasis. A randomized phase 2 trial (N=267) found that deucravacitinib was more effective than placebo in treating chronic plaque psoriasis at doses of 3 to 12 mg daily.¹⁸ The percentage of participants with a 75% or greater reduction from baseline in the psoriasis area and severity index score was 7% with placebo, 9% with deucravacitinib 3 mg every other day (P=.49 vs placebo), 39% with 3 mg once daily (P<.001 vs placebo), 69% with 3 mg twice daily (P<.001 vs placebo), 67% with 6 mg twice daily (P<.001 vs placebo), and 75% with 12 mg once daily (P<.001 vs placebo). The most commonly reported AEs were nasopharyngitis, headache, diarrhea, nausea, and upper respiratory tract infection. Adverse events occurred in 51% of participants in the control group and in 55% to 80% of those in the experimental groups. Additionally, there was 1 reported case of melanoma (stage 0) 96 days after the start of treatment in a patient in the 3-mg once-daily group. Serious AEs occurred in only 0% to 2% of participants who received deucravacitinib.¹⁸

Two phase 3 trials—POETYK PSO-1 and POETYK PSO-2 (N=1686)—found deucravacitinib to be notably more effective than both placebo and apremilast in treating psoriasis.¹⁹ Among participants receiving deucravacitinib 6 mg daily, 58.7% and 53.6% in the 2 respective trials achieved psoriasis area and severity index 75 response vs 12.7% and 9.4% receiving placebo and 35.1% and 40.2% receiving apremilast. Overall, the treatment was well tolerated, with a low rate of discontinuation of deucravacitinib due to AEs (2.4% of patients on deucravacitinib compared to 3.8% on placebo and 5.2% on apremilast). The most frequently observed AEs with deucravacitinib were nasopharyngitis and upper respiratory tract infection. The full results of these trials are expected to be published soon.^19,20

Final Thoughts

Overall, JAK inhibitors are a novel class of therapeutics that may have further success in the treatment of other dermatologic conditions that negatively affect patients’ quality of life and productivity. We should look forward to additional successful trials with these promising medications.

To the Editor:

Oral immunosuppressive therapies are prescribed for moderate to severe atopic dermatitis. Patients often consult YouTube to make informed decisions about these therapies. In the United States, most health-related online searches are initiated through a search engine, which frequently leads to social media sites such as YouTube. Recent studies have examined the reasons why users turn to the Internet for health-related information, indicating that users typically seek specific information regarding health concerns.^1,2 Furthermore, social media platforms such as YouTube are a popular means of sharing health information with the public.^3-5 Currently, YouTube has more than 1 billion registered users, and 30 million health-related videos are watched each day.⁶ Almost one-third of US consumers use YouTube, Facebook, and Twitter to obtain medical information.⁷ YouTube is a versatile tool because of its video-discovery mechanisms such as a keyword-based search engine, video-recommendation system, highlight feature for videos on home pages, and the capacity to embed YouTube videos on various web pages.⁸ Searchers use videos that are short, fast paced, emotion evoking, from credible sources, recently uploaded, and relevant to the searcher for aiding in health decisions.⁹ Furthermore, studies have demonstrated YouTube’s capacity to support a change in attitude and increase users’ knowledge. In fact, YouTube had higher impact on recall, attitudes, and behaviors when compared with written materials on other social media platforms, such as Facebook and Twitter.⁹ We conducted a cross-sectional study to examine the quality of YouTube videos on oral therapies for atopic dermatitis, such as cyclosporine, methotrexate, azathioprine, and mycophenolate mofetil.

On April 23, 2020, we performed 8 searches using a private browser with default filters on YouTube (Figure). Injectables were not included in the analysis, as the YouTube experience on dupilumab previously has been investigated.¹⁰ The top 40 videos from each search were screened by 3 researchers. Duplicates, non–English-language videos, and videos that did not discuss atopic dermatitis or oral therapies were excluded, resulting in 73 videos included in this analysis. Testimonials generated by patients made up 39 of 73 (53.4%) videos. Health care professionals created 23 of 73 (31.5%) videos, and educators with financial interest created 11 of 73 (15.1%) videos. The dates of production for the videos spanned from 2008 to 2020.

Importantly, this analysis is limited by its lack of quality-assessment tools for video-based resources such as JAMA score and DISCERN score.^14,15 However, these metrics have limited ability to evaluate audiovisual elements, indicating the need for novel tools to score their validity.

To the Editor:

Oral immunosuppressive therapies are prescribed for moderate to severe atopic dermatitis. Patients often consult YouTube to make informed decisions about these therapies. In the United States, most health-related online searches are initiated through a search engine, which frequently leads to social media sites such as YouTube. Recent studies have examined the reasons why users turn to the Internet for health-related information, indicating that users typically seek specific information regarding health concerns.^1,2 Furthermore, social media platforms such as YouTube are a popular means of sharing health information with the public.^3-5 Currently, YouTube has more than 1 billion registered users, and 30 million health-related videos are watched each day.⁶ Almost one-third of US consumers use YouTube, Facebook, and Twitter to obtain medical information.⁷ YouTube is a versatile tool because of its video-discovery mechanisms such as a keyword-based search engine, video-recommendation system, highlight feature for videos on home pages, and the capacity to embed YouTube videos on various web pages.⁸ Searchers use videos that are short, fast paced, emotion evoking, from credible sources, recently uploaded, and relevant to the searcher for aiding in health decisions.⁹ Furthermore, studies have demonstrated YouTube’s capacity to support a change in attitude and increase users’ knowledge. In fact, YouTube had higher impact on recall, attitudes, and behaviors when compared with written materials on other social media platforms, such as Facebook and Twitter.⁹ We conducted a cross-sectional study to examine the quality of YouTube videos on oral therapies for atopic dermatitis, such as cyclosporine, methotrexate, azathioprine, and mycophenolate mofetil.

On April 23, 2020, we performed 8 searches using a private browser with default filters on YouTube (Figure). Injectables were not included in the analysis, as the YouTube experience on dupilumab previously has been investigated.¹⁰ The top 40 videos from each search were screened by 3 researchers. Duplicates, non–English-language videos, and videos that did not discuss atopic dermatitis or oral therapies were excluded, resulting in 73 videos included in this analysis. Testimonials generated by patients made up 39 of 73 (53.4%) videos. Health care professionals created 23 of 73 (31.5%) videos, and educators with financial interest created 11 of 73 (15.1%) videos. The dates of production for the videos spanned from 2008 to 2020.

Importantly, this analysis is limited by its lack of quality-assessment tools for video-based resources such as JAMA score and DISCERN score.^14,15 However, these metrics have limited ability to evaluate audiovisual elements, indicating the need for novel tools to score their validity.

To the Editor:

Oral immunosuppressive therapies are prescribed for moderate to severe atopic dermatitis. Patients often consult YouTube to make informed decisions about these therapies. In the United States, most health-related online searches are initiated through a search engine, which frequently leads to social media sites such as YouTube. Recent studies have examined the reasons why users turn to the Internet for health-related information, indicating that users typically seek specific information regarding health concerns.^1,2 Furthermore, social media platforms such as YouTube are a popular means of sharing health information with the public.^3-5 Currently, YouTube has more than 1 billion registered users, and 30 million health-related videos are watched each day.⁶ Almost one-third of US consumers use YouTube, Facebook, and Twitter to obtain medical information.⁷ YouTube is a versatile tool because of its video-discovery mechanisms such as a keyword-based search engine, video-recommendation system, highlight feature for videos on home pages, and the capacity to embed YouTube videos on various web pages.⁸ Searchers use videos that are short, fast paced, emotion evoking, from credible sources, recently uploaded, and relevant to the searcher for aiding in health decisions.⁹ Furthermore, studies have demonstrated YouTube’s capacity to support a change in attitude and increase users’ knowledge. In fact, YouTube had higher impact on recall, attitudes, and behaviors when compared with written materials on other social media platforms, such as Facebook and Twitter.⁹ We conducted a cross-sectional study to examine the quality of YouTube videos on oral therapies for atopic dermatitis, such as cyclosporine, methotrexate, azathioprine, and mycophenolate mofetil.

On April 23, 2020, we performed 8 searches using a private browser with default filters on YouTube (Figure). Injectables were not included in the analysis, as the YouTube experience on dupilumab previously has been investigated.¹⁰ The top 40 videos from each search were screened by 3 researchers. Duplicates, non–English-language videos, and videos that did not discuss atopic dermatitis or oral therapies were excluded, resulting in 73 videos included in this analysis. Testimonials generated by patients made up 39 of 73 (53.4%) videos. Health care professionals created 23 of 73 (31.5%) videos, and educators with financial interest created 11 of 73 (15.1%) videos. The dates of production for the videos spanned from 2008 to 2020.

Importantly, this analysis is limited by its lack of quality-assessment tools for video-based resources such as JAMA score and DISCERN score.^14,15 However, these metrics have limited ability to evaluate audiovisual elements, indicating the need for novel tools to score their validity.

To the Editor:

Atopic dermatitis (eczema) affects approximately 20% of children worldwide.¹ In atopic dermatitis management, patient education is crucial for optimal outcomes.² The COVID-19 pandemic has impacted patient-physician interactions. To ensure safety of patients and physicians, visits may have been canceled, postponed, or conducted virtually, leaving less time for discussion and questions.³ As a consequence, patients may seek information about atopic dermatitis from alternative sources, including YouTube videos. We performed a cross-sectional study to analyze YouTube videos about topical treatments for atopic dermatitis.

During the week of July 16, 2020, we performed 4 private browser YouTube searches with default filters using the following terms: eczema topicals, eczema topical treatments, atopic dermatitis topicals, and atopic dermatitis topical treatments. For video selection, we defined topical treatments as topical corticosteroids, topical calcineurin inhibitors, crisaborole, emollients, wet wraps, and any prospective treatment topically administered. For each of the 4 searches, 2 researchers (A.M. and A.T.) independently examined the top 75 videos, yielding a total of 300 videos. Of them, 98 videos were duplicates, 19 videos were not about atopic dermatitis, and 91 videos were not about topical treatments, leaving a total of 92 videos for analysis (Figure 1).

Although less popular, professional source videos had a significantly higher DISCERN overall quality rating score (question 16) compared to those categorized as nonprofessional source (3.92 vs 1.53; P<.001). In contrast, nonprofessional source videos scored significantly higher on the quality-of-life question (question 13) compared to professional source videos (3.90 vs 2.56; P<.001)(eTable). (Three professional source videos were removed from YouTube before DISCERN scores could be assigned.)

To the Editor:

Atopic dermatitis (eczema) affects approximately 20% of children worldwide.¹ In atopic dermatitis management, patient education is crucial for optimal outcomes.² The COVID-19 pandemic has impacted patient-physician interactions. To ensure safety of patients and physicians, visits may have been canceled, postponed, or conducted virtually, leaving less time for discussion and questions.³ As a consequence, patients may seek information about atopic dermatitis from alternative sources, including YouTube videos. We performed a cross-sectional study to analyze YouTube videos about topical treatments for atopic dermatitis.

During the week of July 16, 2020, we performed 4 private browser YouTube searches with default filters using the following terms: eczema topicals, eczema topical treatments, atopic dermatitis topicals, and atopic dermatitis topical treatments. For video selection, we defined topical treatments as topical corticosteroids, topical calcineurin inhibitors, crisaborole, emollients, wet wraps, and any prospective treatment topically administered. For each of the 4 searches, 2 researchers (A.M. and A.T.) independently examined the top 75 videos, yielding a total of 300 videos. Of them, 98 videos were duplicates, 19 videos were not about atopic dermatitis, and 91 videos were not about topical treatments, leaving a total of 92 videos for analysis (Figure 1).

Although less popular, professional source videos had a significantly higher DISCERN overall quality rating score (question 16) compared to those categorized as nonprofessional source (3.92 vs 1.53; P<.001). In contrast, nonprofessional source videos scored significantly higher on the quality-of-life question (question 13) compared to professional source videos (3.90 vs 2.56; P<.001)(eTable). (Three professional source videos were removed from YouTube before DISCERN scores could be assigned.)

To the Editor:

Atopic dermatitis (eczema) affects approximately 20% of children worldwide.¹ In atopic dermatitis management, patient education is crucial for optimal outcomes.² The COVID-19 pandemic has impacted patient-physician interactions. To ensure safety of patients and physicians, visits may have been canceled, postponed, or conducted virtually, leaving less time for discussion and questions.³ As a consequence, patients may seek information about atopic dermatitis from alternative sources, including YouTube videos. We performed a cross-sectional study to analyze YouTube videos about topical treatments for atopic dermatitis.

During the week of July 16, 2020, we performed 4 private browser YouTube searches with default filters using the following terms: eczema topicals, eczema topical treatments, atopic dermatitis topicals, and atopic dermatitis topical treatments. For video selection, we defined topical treatments as topical corticosteroids, topical calcineurin inhibitors, crisaborole, emollients, wet wraps, and any prospective treatment topically administered. For each of the 4 searches, 2 researchers (A.M. and A.T.) independently examined the top 75 videos, yielding a total of 300 videos. Of them, 98 videos were duplicates, 19 videos were not about atopic dermatitis, and 91 videos were not about topical treatments, leaving a total of 92 videos for analysis (Figure 1).

Although less popular, professional source videos had a significantly higher DISCERN overall quality rating score (question 16) compared to those categorized as nonprofessional source (3.92 vs 1.53; P<.001). In contrast, nonprofessional source videos scored significantly higher on the quality-of-life question (question 13) compared to professional source videos (3.90 vs 2.56; P<.001)(eTable). (Three professional source videos were removed from YouTube before DISCERN scores could be assigned.)

Psoriasis is a chronic and relapsing systemic inflammatory disease that predisposes patients to a host of other conditions. It is believed that these widespread effects are due to chronic inflammation and cytokine activation, which affect multiple body processes and lead to the development of various comorbidities that need to be proactively managed.

In April 2019, the American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) released recommendation guidelines for managing psoriasis in adults with an emphasis on common disease comorbidities, including psoriatic arthritis (PsA), cardiovascular disease (CVD), inflammatory bowel disease (IBD), metabolic syndrome, and mood disorders. Psychosocial wellness, mental health, and quality of life (QOL) measures in relation to psoriatic disease also were discussed.¹

The AAD-NPF guidelines address current screening, monitoring, education, and treatment recommendations for the management of psoriatic comorbidities. The Table and eTable summarize the screening recommendations. These guidelines aim to assist dermatologists with comprehensive disease management by addressing potential extracutaneous manifestations of psoriasis in adults.

Screening and Risk Assessment

Patients with psoriasis should receive a thorough history and physical examination to assess disease severity and risk for potential comorbidities. Patients with greater disease severity—as measured by body surface area (BSA) involvement and type of therapy required—have a greater risk for other disease-related comorbidities, specifically metabolic syndrome, renal disease, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea, uveitis, IBD, malignancy, and increased mortality.² Because the likelihood of comorbidities is greatest with severe disease, more frequent monitoring is recommended for these patients.

Psoriatic Arthritis

Patients with psoriasis need to be evaluated for PsA at every visit. Patients presenting with signs and symptoms suspicious for PsA—joint swelling, peripheral joint involvement, and joint inflammation—warrant further evaluation and consultation. Early detection and treatment of PsA is essential for preventing unnecessary suffering and progressive joint destruction.³

There are several PsA screening questionnaires currently available, including the Psoriatic Arthritis Screening Evaluation, Psoriasis Epidemiology Screening Tool, and Toronto Psoriatic Arthritis Screen. No significant differences in sensitivity and specificity were found among these questionnaires when using the Classification Criteria for Psoriatic Arthritis as the gold standard. All 3 questionnaires—the Psoriatic Arthritis Screening Evaluation and the Psoriasis Epidemiology Screening Tool were developed for use in dermatology and rheumatology clinics, and the Toronto Psoriatic Arthritis Screen was developed for use in the primary care setting—were found to be effective in dermatology/rheumatology clinics and primary care clinics, respectively.³ False-positive results predominantly were seen in patients with degenerative joint disease or osteoarthritis. Dermatologists should conduct a thorough physical examination to distinguish PsA from degenerative joint disease. Imaging and laboratory tests to evaluate for signs of systemic inflammation (erythrocyte sedimentation rate, C-reactive protein) also can be helpful in distinguishing the 2 conditions; however, these metrics have not been shown to contribute to PsA diagnosis.¹ Full rheumatologic consultation is warranted in challenging cases.

Cardiovascular Disease

The American Heart Association and the American College of Cardiology have identified chronic inflammatory states, such as psoriasis, as inducing factors that predispose patients to CVD. Many studies have found an association among psoriasis, coronary artery disease, myocardial infarction (MI), and stroke.^4-7 It is strongly recommended that dermatologists educate patients of their increased risk for CVD, given the association between psoriasis and major adverse cardiovascular events (eg, stroke, heart failure, MI) and cardiovascular health. However, patients with congestive heart failure were found to have an increased risk of mortality associated with use of tumor necrosis factor (TNF) α inhibitors (P=.016).⁸ Thus, TNF inhibitors are contraindicated in patients with New York Heart Association Class III or Class IV congestive heart failure.⁹

Primary care physicians (PCPs) are recommended to screen patients for CVD risk factors using height, weight, blood pressure, blood glucose, hemoglobin A_1C, lipid levels, abdominal circumference, and body mass index (BMI). Lifestyle modifications such as smoking cessation, exercise, and dietary changes are encouraged to achieve and maintain a normal BMI.

Dermatologists also need to give special consideration to comorbidities when selecting medications and/or therapies for disease management. Patients on TNF inhibitors have a lower risk for MI compared with patients using topical medications, phototherapy, and other oral agents.¹⁰ Additionally, patients on TNF inhibitors have a lower risk for occurrence of major adverse cardiovascular events compared with patients treated with methotrexate or phototherapy.^11,12

Metabolic Syndrome

Numerous studies have demonstrated an association between psoriasis and metabolic syndrome. Patients with increased BSA involvement and psoriasis area and severity index scores have a higher prevalence of metabolic syndrome.¹³ Patients with psoriasis have an increased risk for the following conditions compared to controls: obesity (38% vs 31%; odds ratio [OR], 1.38; 95% CI, 1.29-1.48), elevated triglycerides (36% vs 28%; OR, 1.49; 95% CI, 1.39-1.60), hypertension (31% vs 28%; OR, 1.20; 95% CI, 1.11-12.9), and elevated glucose levels (22% vs 16%; OR, 1.44; 95% CI, 1.33-1.56).¹⁴ Dermatologists are strongly recommended to inform patients about the risk for metabolic syndrome and to encourage the measurement of blood pressure, waist circumference, fasting blood glucose, hemoglobin A_1C, and fasting lipid levels with their PCP when indicated. Body mass index and waist circumference also should be measured annually in patients with moderate to severe psoriasis because of the association with disease severity.

The association between psoriasis and weight loss has been analyzed in several studies. Weight loss, particularly in obese patients, has been shown to improve psoriasis severity, as measured by psoriasis area and severity index score and QOL measures.¹⁵ Another study found that gastric bypass was associated with a significant risk reduction in the development of psoriasis (P=.004) and the disease prognosis (P=.02 for severe psoriasis; P=.01 for PsA).¹⁶ Therefore, patients with moderate to severe psoriasis are recommended to have their obesity status determined according to national guidelines. For patients with a BMI above 40 kg/m² and standard weight-loss measures fail, bariatric surgery is recommended. Additionally, the impact of psoriasis medications on weight has been studied. Apremilast has been associated with weight loss, whereas etanercept and infliximab have been linked to weight gain.^17,18

An association between psoriasis and hypertension also has been demonstrated by studies, especially among patients with severe disease. Therefore, patients with moderate to severe psoriasis are recommended to have their blood pressure evaluated according to national guidelines, and those with a blood pressure of 140/90 mm Hg or higher should be referred to their PCP for assessment and treatment. Current evidence does not support restrictions on antihypertensive medications in patients with psoriasis. Physicians should be aware of the potential for cyclosporine to induce hypertension, which should be treated, specifically with amlodipine.¹⁹

Many studies have demonstrated an association between psoriasis and dyslipidemia, though the results are somewhat conflicting. In 2018, the American Heart Association and the American College of Cardiology deemed psoriasis as an atherosclerotic CVD risk-enhancing condition, favoring early initiation of statin therapy. Because dyslipidemia plays a prominent role in atherosclerosis and CVD, patients with moderate to severe psoriasis are recommended to undergo periodic screening with lipid tests (eg, fasting total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides).²⁰ Patients with elevated fasting triglycerides or low-density lipoprotein cholesterol should be referred to their PCP for further management. Certain psoriasis medications also have been linked to dyslipidemia. Acitretin and cyclosporine are known to adversely affect lipid levels, so patients treated with either agent should undergo routine monitoring of serum lipid levels.

Psoriasis is strongly associated with diabetes mellitus. Because of the increased risk for diabetes in patients with severe disease, regular monitoring of fasting blood glucose and/or hemoglobin A_1C levels in patients with moderate to severe psoriasis is recommended. Patients who meet criteria for prediabetes or diabetes should be referred to their PCP for further assessment and management.^21,22

Mood Disorders

Psoriasis affects QOL and can have a major impact on patients’ interpersonal relationships. Studies have shown an association between psoriasis and mood disorders, specifically depression and anxiety. Unfortunately, patients with mood disorders are less likely to seek intervention for their skin disease, which poses a tremendous treatment barrier. Dermatologists should regularly monitor patients for psychiatric symptoms so that resources and treatments can be offered.

Certain psoriasis therapies have been shown to help alleviate associated depression and anxiety. Improvements in Beck Depression Inventory and Hamilton Depression Rating Scale scores were seen with etanercept.²³ Adalimumab and ustekinumab showed improvement in Dermatology Life Quality Index compared with placebo.^24,25 Patients receiving Goeckerman treatment also had improvement in anxiety and depression scores compared with conventional therapy.²⁶ Biologic medications had the largest impact on improving depression symptoms compared with conventional systemic therapy and phototherapy.²⁷ The recommendations support use of biologics and the Goeckerman regimen for the concomitant treatment of mood disorders and psoriasis.

Renal Disease

Studies have supported an association between psoriasis and chronic kidney disease (CKD), independent of risk factors including vascular disease, hypertension, and diabetes. The prevalence of moderate to advanced CKD also has been found to be directly related to increasing BSA affected by psoriasis.²⁸ Patients should receive testing of blood urea nitrogen, creatinine, and urine microalbumin levels to assess for occult renal disease. In addition, physicians should be cautious when prescribing nephrotoxic drugs (nonsteroidal anti-inflammatory drugs and cyclosporine) and renally excreted agents (methotrexate and apremilast) because of the risk for underlying renal disease in patients with psoriasis. If newly acquired renal disease is suspected, physicians should withhold the offending agents. Patients with psoriasis with CKD are recommended to follow up with their PCP or nephrologist for evaluation and management.

Pulmonary Disease

Psoriasis also has an independent association with COPD. Patients with psoriasis have a higher likelihood of developing COPD (hazard ratio, 2.35; 95% CI, 1.42-3.89; P<.01) than controls.²⁹ The prevalence of COPD also was found to correlate with psoriasis severity. Dermatologists should educate patients about the association between smoking and psoriasis as well as advise patients to discontinue smoking to reduce their risk for developing COPD and cancer.

Patients with psoriasis also are at an increased risk for obstructive sleep apnea. Obstructive sleep apnea should be considered in patients with risk factors including snoring, obesity, hypertension, or diabetes.

Inflammatory Bowel Disease

Patients with psoriasis have an increased risk for developing IBD. The prevalence ratios of both Crohn disease (2.49) and ulcerative colitis (1.64) are increased in patients with psoriasis relative to patients without psoriasis.³⁰ Physicians need to be aware of the association between psoriasis and IBD and the effect that their coexistence may have on treatment choice for patients.

Adalimumab and infliximab are approved for the treatment of IBD, and certolizumab and ustekinumab are approved for Crohn disease. Use of TNF inhibitors in patients with IBD may cause psoriasiform lesions to develop.³¹ Nonetheless, treatment should be individualized and psoriasiform lesions treated with standard psoriasis measures. Psoriasis patients with IBD are recommended to avoid IL-17–inhibitor therapy, given its potential to worsen IBD flares.

Malignancy

Psoriasis patients aged 0 to 79 years have a greater overall risk for malignancy compared with patients without psoriasis.³² Patients with psoriasis have an increased risk for respiratory tract cancer, upper aerodigestive tract cancer, urinary tract cancer, and non-Hodgkin lymphoma.³³ A mild association exists between PsA and lymphoma, nonmelanoma skin cancer (NMSC), and lung cancer.³⁴ More severe psoriasis is associated with greater risk for lymphoma and NMSC. Dermatologists are recommended to educate patients on their risk for certain malignancies and to refer patients to specialists upon suspicion of malignancy.

Risk for malignancy has been shown to be affected by psoriasis treatments. Patients treated with UVB have reduced overall cancer rates for all age groups (hazard ratio, 0.52; P=.3), while those treated with psoralen plus UVA have an increased incidence of squamous cell carcinoma.^32,33 Adalimumab was correlated with increased risk for NMSC in patients with psoriasis but did not have an increased risk for all cancers collectively when used for various immune-mediated inflammatory diseases.³⁵ In contrast, a meta-analysis of randomized clinical trials found no association with TNF inhibitor use and NMSC.³⁶ Ustekinumab had no association with malignancy.³⁷ Treatment history should be elucidated because of higher rates of squamous cell carcinoma in patients with prior psoralen plus UVA, cyclosporine, or methotrexate use.³³ To address malignancy risk, patients with psoriasis should undergo regular screenings for skin cancer and follow national guidelines for age-appropriate cancer screenings.

Lifestyle Choices and QOL

A crucial aspect of successful psoriasis management is patient education. The strongest recommendations support lifestyle changes, such as smoking cessation and limitation of alcohol use. A tactful discussion regarding substance use, work productivity, interpersonal relationships, and sexual function can address substantial effects of psoriasis on QOL so that support and resources can be provided.

Final Thoughts

Management of psoriasis is multifaceted and involves screening, education, monitoring, and collaboration with PCPs and specialists. Regular follow-up with a dermatologist and PCP is strongly recommended for patients with psoriasis given the systemic nature of the disease. The 2019 AAD-NPF recommendations provide important information for dermatologists to coordinate care for complicated psoriasis cases, but clinical judgment is paramount when making medical decisions. The consideration of comorbidities is critical for developing a comprehensive treatment approach, and this approach will lead to better health outcomes and improved QOL for patients with psoriasis.

Psoriasis is a chronic and relapsing systemic inflammatory disease that predisposes patients to a host of other conditions. It is believed that these widespread effects are due to chronic inflammation and cytokine activation, which affect multiple body processes and lead to the development of various comorbidities that need to be proactively managed.

In April 2019, the American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) released recommendation guidelines for managing psoriasis in adults with an emphasis on common disease comorbidities, including psoriatic arthritis (PsA), cardiovascular disease (CVD), inflammatory bowel disease (IBD), metabolic syndrome, and mood disorders. Psychosocial wellness, mental health, and quality of life (QOL) measures in relation to psoriatic disease also were discussed.¹

The AAD-NPF guidelines address current screening, monitoring, education, and treatment recommendations for the management of psoriatic comorbidities. The Table and eTable summarize the screening recommendations. These guidelines aim to assist dermatologists with comprehensive disease management by addressing potential extracutaneous manifestations of psoriasis in adults.

Screening and Risk Assessment

Patients with psoriasis should receive a thorough history and physical examination to assess disease severity and risk for potential comorbidities. Patients with greater disease severity—as measured by body surface area (BSA) involvement and type of therapy required—have a greater risk for other disease-related comorbidities, specifically metabolic syndrome, renal disease, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea, uveitis, IBD, malignancy, and increased mortality.² Because the likelihood of comorbidities is greatest with severe disease, more frequent monitoring is recommended for these patients.

Psoriatic Arthritis

Patients with psoriasis need to be evaluated for PsA at every visit. Patients presenting with signs and symptoms suspicious for PsA—joint swelling, peripheral joint involvement, and joint inflammation—warrant further evaluation and consultation. Early detection and treatment of PsA is essential for preventing unnecessary suffering and progressive joint destruction.³

There are several PsA screening questionnaires currently available, including the Psoriatic Arthritis Screening Evaluation, Psoriasis Epidemiology Screening Tool, and Toronto Psoriatic Arthritis Screen. No significant differences in sensitivity and specificity were found among these questionnaires when using the Classification Criteria for Psoriatic Arthritis as the gold standard. All 3 questionnaires—the Psoriatic Arthritis Screening Evaluation and the Psoriasis Epidemiology Screening Tool were developed for use in dermatology and rheumatology clinics, and the Toronto Psoriatic Arthritis Screen was developed for use in the primary care setting—were found to be effective in dermatology/rheumatology clinics and primary care clinics, respectively.³ False-positive results predominantly were seen in patients with degenerative joint disease or osteoarthritis. Dermatologists should conduct a thorough physical examination to distinguish PsA from degenerative joint disease. Imaging and laboratory tests to evaluate for signs of systemic inflammation (erythrocyte sedimentation rate, C-reactive protein) also can be helpful in distinguishing the 2 conditions; however, these metrics have not been shown to contribute to PsA diagnosis.¹ Full rheumatologic consultation is warranted in challenging cases.

Cardiovascular Disease

The American Heart Association and the American College of Cardiology have identified chronic inflammatory states, such as psoriasis, as inducing factors that predispose patients to CVD. Many studies have found an association among psoriasis, coronary artery disease, myocardial infarction (MI), and stroke.^4-7 It is strongly recommended that dermatologists educate patients of their increased risk for CVD, given the association between psoriasis and major adverse cardiovascular events (eg, stroke, heart failure, MI) and cardiovascular health. However, patients with congestive heart failure were found to have an increased risk of mortality associated with use of tumor necrosis factor (TNF) α inhibitors (P=.016).⁸ Thus, TNF inhibitors are contraindicated in patients with New York Heart Association Class III or Class IV congestive heart failure.⁹

Primary care physicians (PCPs) are recommended to screen patients for CVD risk factors using height, weight, blood pressure, blood glucose, hemoglobin A_1C, lipid levels, abdominal circumference, and body mass index (BMI). Lifestyle modifications such as smoking cessation, exercise, and dietary changes are encouraged to achieve and maintain a normal BMI.

Dermatologists also need to give special consideration to comorbidities when selecting medications and/or therapies for disease management. Patients on TNF inhibitors have a lower risk for MI compared with patients using topical medications, phototherapy, and other oral agents.¹⁰ Additionally, patients on TNF inhibitors have a lower risk for occurrence of major adverse cardiovascular events compared with patients treated with methotrexate or phototherapy.^11,12

Metabolic Syndrome

Numerous studies have demonstrated an association between psoriasis and metabolic syndrome. Patients with increased BSA involvement and psoriasis area and severity index scores have a higher prevalence of metabolic syndrome.¹³ Patients with psoriasis have an increased risk for the following conditions compared to controls: obesity (38% vs 31%; odds ratio [OR], 1.38; 95% CI, 1.29-1.48), elevated triglycerides (36% vs 28%; OR, 1.49; 95% CI, 1.39-1.60), hypertension (31% vs 28%; OR, 1.20; 95% CI, 1.11-12.9), and elevated glucose levels (22% vs 16%; OR, 1.44; 95% CI, 1.33-1.56).¹⁴ Dermatologists are strongly recommended to inform patients about the risk for metabolic syndrome and to encourage the measurement of blood pressure, waist circumference, fasting blood glucose, hemoglobin A_1C, and fasting lipid levels with their PCP when indicated. Body mass index and waist circumference also should be measured annually in patients with moderate to severe psoriasis because of the association with disease severity.

The association between psoriasis and weight loss has been analyzed in several studies. Weight loss, particularly in obese patients, has been shown to improve psoriasis severity, as measured by psoriasis area and severity index score and QOL measures.¹⁵ Another study found that gastric bypass was associated with a significant risk reduction in the development of psoriasis (P=.004) and the disease prognosis (P=.02 for severe psoriasis; P=.01 for PsA).¹⁶ Therefore, patients with moderate to severe psoriasis are recommended to have their obesity status determined according to national guidelines. For patients with a BMI above 40 kg/m² and standard weight-loss measures fail, bariatric surgery is recommended. Additionally, the impact of psoriasis medications on weight has been studied. Apremilast has been associated with weight loss, whereas etanercept and infliximab have been linked to weight gain.^17,18

An association between psoriasis and hypertension also has been demonstrated by studies, especially among patients with severe disease. Therefore, patients with moderate to severe psoriasis are recommended to have their blood pressure evaluated according to national guidelines, and those with a blood pressure of 140/90 mm Hg or higher should be referred to their PCP for assessment and treatment. Current evidence does not support restrictions on antihypertensive medications in patients with psoriasis. Physicians should be aware of the potential for cyclosporine to induce hypertension, which should be treated, specifically with amlodipine.¹⁹

Many studies have demonstrated an association between psoriasis and dyslipidemia, though the results are somewhat conflicting. In 2018, the American Heart Association and the American College of Cardiology deemed psoriasis as an atherosclerotic CVD risk-enhancing condition, favoring early initiation of statin therapy. Because dyslipidemia plays a prominent role in atherosclerosis and CVD, patients with moderate to severe psoriasis are recommended to undergo periodic screening with lipid tests (eg, fasting total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides).²⁰ Patients with elevated fasting triglycerides or low-density lipoprotein cholesterol should be referred to their PCP for further management. Certain psoriasis medications also have been linked to dyslipidemia. Acitretin and cyclosporine are known to adversely affect lipid levels, so patients treated with either agent should undergo routine monitoring of serum lipid levels.

Psoriasis is strongly associated with diabetes mellitus. Because of the increased risk for diabetes in patients with severe disease, regular monitoring of fasting blood glucose and/or hemoglobin A_1C levels in patients with moderate to severe psoriasis is recommended. Patients who meet criteria for prediabetes or diabetes should be referred to their PCP for further assessment and management.^21,22

Mood Disorders

Psoriasis affects QOL and can have a major impact on patients’ interpersonal relationships. Studies have shown an association between psoriasis and mood disorders, specifically depression and anxiety. Unfortunately, patients with mood disorders are less likely to seek intervention for their skin disease, which poses a tremendous treatment barrier. Dermatologists should regularly monitor patients for psychiatric symptoms so that resources and treatments can be offered.

Certain psoriasis therapies have been shown to help alleviate associated depression and anxiety. Improvements in Beck Depression Inventory and Hamilton Depression Rating Scale scores were seen with etanercept.²³ Adalimumab and ustekinumab showed improvement in Dermatology Life Quality Index compared with placebo.^24,25 Patients receiving Goeckerman treatment also had improvement in anxiety and depression scores compared with conventional therapy.²⁶ Biologic medications had the largest impact on improving depression symptoms compared with conventional systemic therapy and phototherapy.²⁷ The recommendations support use of biologics and the Goeckerman regimen for the concomitant treatment of mood disorders and psoriasis.

Renal Disease

Studies have supported an association between psoriasis and chronic kidney disease (CKD), independent of risk factors including vascular disease, hypertension, and diabetes. The prevalence of moderate to advanced CKD also has been found to be directly related to increasing BSA affected by psoriasis.²⁸ Patients should receive testing of blood urea nitrogen, creatinine, and urine microalbumin levels to assess for occult renal disease. In addition, physicians should be cautious when prescribing nephrotoxic drugs (nonsteroidal anti-inflammatory drugs and cyclosporine) and renally excreted agents (methotrexate and apremilast) because of the risk for underlying renal disease in patients with psoriasis. If newly acquired renal disease is suspected, physicians should withhold the offending agents. Patients with psoriasis with CKD are recommended to follow up with their PCP or nephrologist for evaluation and management.

Pulmonary Disease

Psoriasis also has an independent association with COPD. Patients with psoriasis have a higher likelihood of developing COPD (hazard ratio, 2.35; 95% CI, 1.42-3.89; P<.01) than controls.²⁹ The prevalence of COPD also was found to correlate with psoriasis severity. Dermatologists should educate patients about the association between smoking and psoriasis as well as advise patients to discontinue smoking to reduce their risk for developing COPD and cancer.

Patients with psoriasis also are at an increased risk for obstructive sleep apnea. Obstructive sleep apnea should be considered in patients with risk factors including snoring, obesity, hypertension, or diabetes.

Inflammatory Bowel Disease

Patients with psoriasis have an increased risk for developing IBD. The prevalence ratios of both Crohn disease (2.49) and ulcerative colitis (1.64) are increased in patients with psoriasis relative to patients without psoriasis.³⁰ Physicians need to be aware of the association between psoriasis and IBD and the effect that their coexistence may have on treatment choice for patients.

Adalimumab and infliximab are approved for the treatment of IBD, and certolizumab and ustekinumab are approved for Crohn disease. Use of TNF inhibitors in patients with IBD may cause psoriasiform lesions to develop.³¹ Nonetheless, treatment should be individualized and psoriasiform lesions treated with standard psoriasis measures. Psoriasis patients with IBD are recommended to avoid IL-17–inhibitor therapy, given its potential to worsen IBD flares.

Malignancy

Psoriasis patients aged 0 to 79 years have a greater overall risk for malignancy compared with patients without psoriasis.³² Patients with psoriasis have an increased risk for respiratory tract cancer, upper aerodigestive tract cancer, urinary tract cancer, and non-Hodgkin lymphoma.³³ A mild association exists between PsA and lymphoma, nonmelanoma skin cancer (NMSC), and lung cancer.³⁴ More severe psoriasis is associated with greater risk for lymphoma and NMSC. Dermatologists are recommended to educate patients on their risk for certain malignancies and to refer patients to specialists upon suspicion of malignancy.

Risk for malignancy has been shown to be affected by psoriasis treatments. Patients treated with UVB have reduced overall cancer rates for all age groups (hazard ratio, 0.52; P=.3), while those treated with psoralen plus UVA have an increased incidence of squamous cell carcinoma.^32,33 Adalimumab was correlated with increased risk for NMSC in patients with psoriasis but did not have an increased risk for all cancers collectively when used for various immune-mediated inflammatory diseases.³⁵ In contrast, a meta-analysis of randomized clinical trials found no association with TNF inhibitor use and NMSC.³⁶ Ustekinumab had no association with malignancy.³⁷ Treatment history should be elucidated because of higher rates of squamous cell carcinoma in patients with prior psoralen plus UVA, cyclosporine, or methotrexate use.³³ To address malignancy risk, patients with psoriasis should undergo regular screenings for skin cancer and follow national guidelines for age-appropriate cancer screenings.

Lifestyle Choices and QOL

A crucial aspect of successful psoriasis management is patient education. The strongest recommendations support lifestyle changes, such as smoking cessation and limitation of alcohol use. A tactful discussion regarding substance use, work productivity, interpersonal relationships, and sexual function can address substantial effects of psoriasis on QOL so that support and resources can be provided.

Final Thoughts

Management of psoriasis is multifaceted and involves screening, education, monitoring, and collaboration with PCPs and specialists. Regular follow-up with a dermatologist and PCP is strongly recommended for patients with psoriasis given the systemic nature of the disease. The 2019 AAD-NPF recommendations provide important information for dermatologists to coordinate care for complicated psoriasis cases, but clinical judgment is paramount when making medical decisions. The consideration of comorbidities is critical for developing a comprehensive treatment approach, and this approach will lead to better health outcomes and improved QOL for patients with psoriasis.

Psoriasis is a chronic and relapsing systemic inflammatory disease that predisposes patients to a host of other conditions. It is believed that these widespread effects are due to chronic inflammation and cytokine activation, which affect multiple body processes and lead to the development of various comorbidities that need to be proactively managed.

In April 2019, the American Academy of Dermatology (AAD) and National Psoriasis Foundation (NPF) released recommendation guidelines for managing psoriasis in adults with an emphasis on common disease comorbidities, including psoriatic arthritis (PsA), cardiovascular disease (CVD), inflammatory bowel disease (IBD), metabolic syndrome, and mood disorders. Psychosocial wellness, mental health, and quality of life (QOL) measures in relation to psoriatic disease also were discussed.¹

The AAD-NPF guidelines address current screening, monitoring, education, and treatment recommendations for the management of psoriatic comorbidities. The Table and eTable summarize the screening recommendations. These guidelines aim to assist dermatologists with comprehensive disease management by addressing potential extracutaneous manifestations of psoriasis in adults.

Screening and Risk Assessment

Patients with psoriasis should receive a thorough history and physical examination to assess disease severity and risk for potential comorbidities. Patients with greater disease severity—as measured by body surface area (BSA) involvement and type of therapy required—have a greater risk for other disease-related comorbidities, specifically metabolic syndrome, renal disease, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea, uveitis, IBD, malignancy, and increased mortality.² Because the likelihood of comorbidities is greatest with severe disease, more frequent monitoring is recommended for these patients.

Psoriatic Arthritis

Patients with psoriasis need to be evaluated for PsA at every visit. Patients presenting with signs and symptoms suspicious for PsA—joint swelling, peripheral joint involvement, and joint inflammation—warrant further evaluation and consultation. Early detection and treatment of PsA is essential for preventing unnecessary suffering and progressive joint destruction.³

There are several PsA screening questionnaires currently available, including the Psoriatic Arthritis Screening Evaluation, Psoriasis Epidemiology Screening Tool, and Toronto Psoriatic Arthritis Screen. No significant differences in sensitivity and specificity were found among these questionnaires when using the Classification Criteria for Psoriatic Arthritis as the gold standard. All 3 questionnaires—the Psoriatic Arthritis Screening Evaluation and the Psoriasis Epidemiology Screening Tool were developed for use in dermatology and rheumatology clinics, and the Toronto Psoriatic Arthritis Screen was developed for use in the primary care setting—were found to be effective in dermatology/rheumatology clinics and primary care clinics, respectively.³ False-positive results predominantly were seen in patients with degenerative joint disease or osteoarthritis. Dermatologists should conduct a thorough physical examination to distinguish PsA from degenerative joint disease. Imaging and laboratory tests to evaluate for signs of systemic inflammation (erythrocyte sedimentation rate, C-reactive protein) also can be helpful in distinguishing the 2 conditions; however, these metrics have not been shown to contribute to PsA diagnosis.¹ Full rheumatologic consultation is warranted in challenging cases.

Cardiovascular Disease

The American Heart Association and the American College of Cardiology have identified chronic inflammatory states, such as psoriasis, as inducing factors that predispose patients to CVD. Many studies have found an association among psoriasis, coronary artery disease, myocardial infarction (MI), and stroke.^4-7 It is strongly recommended that dermatologists educate patients of their increased risk for CVD, given the association between psoriasis and major adverse cardiovascular events (eg, stroke, heart failure, MI) and cardiovascular health. However, patients with congestive heart failure were found to have an increased risk of mortality associated with use of tumor necrosis factor (TNF) α inhibitors (P=.016).⁸ Thus, TNF inhibitors are contraindicated in patients with New York Heart Association Class III or Class IV congestive heart failure.⁹

Primary care physicians (PCPs) are recommended to screen patients for CVD risk factors using height, weight, blood pressure, blood glucose, hemoglobin A_1C, lipid levels, abdominal circumference, and body mass index (BMI). Lifestyle modifications such as smoking cessation, exercise, and dietary changes are encouraged to achieve and maintain a normal BMI.

Dermatologists also need to give special consideration to comorbidities when selecting medications and/or therapies for disease management. Patients on TNF inhibitors have a lower risk for MI compared with patients using topical medications, phototherapy, and other oral agents.¹⁰ Additionally, patients on TNF inhibitors have a lower risk for occurrence of major adverse cardiovascular events compared with patients treated with methotrexate or phototherapy.^11,12

Metabolic Syndrome

Numerous studies have demonstrated an association between psoriasis and metabolic syndrome. Patients with increased BSA involvement and psoriasis area and severity index scores have a higher prevalence of metabolic syndrome.¹³ Patients with psoriasis have an increased risk for the following conditions compared to controls: obesity (38% vs 31%; odds ratio [OR], 1.38; 95% CI, 1.29-1.48), elevated triglycerides (36% vs 28%; OR, 1.49; 95% CI, 1.39-1.60), hypertension (31% vs 28%; OR, 1.20; 95% CI, 1.11-12.9), and elevated glucose levels (22% vs 16%; OR, 1.44; 95% CI, 1.33-1.56).¹⁴ Dermatologists are strongly recommended to inform patients about the risk for metabolic syndrome and to encourage the measurement of blood pressure, waist circumference, fasting blood glucose, hemoglobin A_1C, and fasting lipid levels with their PCP when indicated. Body mass index and waist circumference also should be measured annually in patients with moderate to severe psoriasis because of the association with disease severity.

The association between psoriasis and weight loss has been analyzed in several studies. Weight loss, particularly in obese patients, has been shown to improve psoriasis severity, as measured by psoriasis area and severity index score and QOL measures.¹⁵ Another study found that gastric bypass was associated with a significant risk reduction in the development of psoriasis (P=.004) and the disease prognosis (P=.02 for severe psoriasis; P=.01 for PsA).¹⁶ Therefore, patients with moderate to severe psoriasis are recommended to have their obesity status determined according to national guidelines. For patients with a BMI above 40 kg/m² and standard weight-loss measures fail, bariatric surgery is recommended. Additionally, the impact of psoriasis medications on weight has been studied. Apremilast has been associated with weight loss, whereas etanercept and infliximab have been linked to weight gain.^17,18

An association between psoriasis and hypertension also has been demonstrated by studies, especially among patients with severe disease. Therefore, patients with moderate to severe psoriasis are recommended to have their blood pressure evaluated according to national guidelines, and those with a blood pressure of 140/90 mm Hg or higher should be referred to their PCP for assessment and treatment. Current evidence does not support restrictions on antihypertensive medications in patients with psoriasis. Physicians should be aware of the potential for cyclosporine to induce hypertension, which should be treated, specifically with amlodipine.¹⁹

Many studies have demonstrated an association between psoriasis and dyslipidemia, though the results are somewhat conflicting. In 2018, the American Heart Association and the American College of Cardiology deemed psoriasis as an atherosclerotic CVD risk-enhancing condition, favoring early initiation of statin therapy. Because dyslipidemia plays a prominent role in atherosclerosis and CVD, patients with moderate to severe psoriasis are recommended to undergo periodic screening with lipid tests (eg, fasting total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides).²⁰ Patients with elevated fasting triglycerides or low-density lipoprotein cholesterol should be referred to their PCP for further management. Certain psoriasis medications also have been linked to dyslipidemia. Acitretin and cyclosporine are known to adversely affect lipid levels, so patients treated with either agent should undergo routine monitoring of serum lipid levels.

Psoriasis is strongly associated with diabetes mellitus. Because of the increased risk for diabetes in patients with severe disease, regular monitoring of fasting blood glucose and/or hemoglobin A_1C levels in patients with moderate to severe psoriasis is recommended. Patients who meet criteria for prediabetes or diabetes should be referred to their PCP for further assessment and management.^21,22

Mood Disorders

Psoriasis affects QOL and can have a major impact on patients’ interpersonal relationships. Studies have shown an association between psoriasis and mood disorders, specifically depression and anxiety. Unfortunately, patients with mood disorders are less likely to seek intervention for their skin disease, which poses a tremendous treatment barrier. Dermatologists should regularly monitor patients for psychiatric symptoms so that resources and treatments can be offered.

Certain psoriasis therapies have been shown to help alleviate associated depression and anxiety. Improvements in Beck Depression Inventory and Hamilton Depression Rating Scale scores were seen with etanercept.²³ Adalimumab and ustekinumab showed improvement in Dermatology Life Quality Index compared with placebo.^24,25 Patients receiving Goeckerman treatment also had improvement in anxiety and depression scores compared with conventional therapy.²⁶ Biologic medications had the largest impact on improving depression symptoms compared with conventional systemic therapy and phototherapy.²⁷ The recommendations support use of biologics and the Goeckerman regimen for the concomitant treatment of mood disorders and psoriasis.

Renal Disease

Studies have supported an association between psoriasis and chronic kidney disease (CKD), independent of risk factors including vascular disease, hypertension, and diabetes. The prevalence of moderate to advanced CKD also has been found to be directly related to increasing BSA affected by psoriasis.²⁸ Patients should receive testing of blood urea nitrogen, creatinine, and urine microalbumin levels to assess for occult renal disease. In addition, physicians should be cautious when prescribing nephrotoxic drugs (nonsteroidal anti-inflammatory drugs and cyclosporine) and renally excreted agents (methotrexate and apremilast) because of the risk for underlying renal disease in patients with psoriasis. If newly acquired renal disease is suspected, physicians should withhold the offending agents. Patients with psoriasis with CKD are recommended to follow up with their PCP or nephrologist for evaluation and management.

Pulmonary Disease

Psoriasis also has an independent association with COPD. Patients with psoriasis have a higher likelihood of developing COPD (hazard ratio, 2.35; 95% CI, 1.42-3.89; P<.01) than controls.²⁹ The prevalence of COPD also was found to correlate with psoriasis severity. Dermatologists should educate patients about the association between smoking and psoriasis as well as advise patients to discontinue smoking to reduce their risk for developing COPD and cancer.

Patients with psoriasis also are at an increased risk for obstructive sleep apnea. Obstructive sleep apnea should be considered in patients with risk factors including snoring, obesity, hypertension, or diabetes.

Inflammatory Bowel Disease

Patients with psoriasis have an increased risk for developing IBD. The prevalence ratios of both Crohn disease (2.49) and ulcerative colitis (1.64) are increased in patients with psoriasis relative to patients without psoriasis.³⁰ Physicians need to be aware of the association between psoriasis and IBD and the effect that their coexistence may have on treatment choice for patients.

Adalimumab and infliximab are approved for the treatment of IBD, and certolizumab and ustekinumab are approved for Crohn disease. Use of TNF inhibitors in patients with IBD may cause psoriasiform lesions to develop.³¹ Nonetheless, treatment should be individualized and psoriasiform lesions treated with standard psoriasis measures. Psoriasis patients with IBD are recommended to avoid IL-17–inhibitor therapy, given its potential to worsen IBD flares.

Malignancy

Psoriasis patients aged 0 to 79 years have a greater overall risk for malignancy compared with patients without psoriasis.³² Patients with psoriasis have an increased risk for respiratory tract cancer, upper aerodigestive tract cancer, urinary tract cancer, and non-Hodgkin lymphoma.³³ A mild association exists between PsA and lymphoma, nonmelanoma skin cancer (NMSC), and lung cancer.³⁴ More severe psoriasis is associated with greater risk for lymphoma and NMSC. Dermatologists are recommended to educate patients on their risk for certain malignancies and to refer patients to specialists upon suspicion of malignancy.

Risk for malignancy has been shown to be affected by psoriasis treatments. Patients treated with UVB have reduced overall cancer rates for all age groups (hazard ratio, 0.52; P=.3), while those treated with psoralen plus UVA have an increased incidence of squamous cell carcinoma.^32,33 Adalimumab was correlated with increased risk for NMSC in patients with psoriasis but did not have an increased risk for all cancers collectively when used for various immune-mediated inflammatory diseases.³⁵ In contrast, a meta-analysis of randomized clinical trials found no association with TNF inhibitor use and NMSC.³⁶ Ustekinumab had no association with malignancy.³⁷ Treatment history should be elucidated because of higher rates of squamous cell carcinoma in patients with prior psoralen plus UVA, cyclosporine, or methotrexate use.³³ To address malignancy risk, patients with psoriasis should undergo regular screenings for skin cancer and follow national guidelines for age-appropriate cancer screenings.

Lifestyle Choices and QOL

A crucial aspect of successful psoriasis management is patient education. The strongest recommendations support lifestyle changes, such as smoking cessation and limitation of alcohol use. A tactful discussion regarding substance use, work productivity, interpersonal relationships, and sexual function can address substantial effects of psoriasis on QOL so that support and resources can be provided.

Final Thoughts

Management of psoriasis is multifaceted and involves screening, education, monitoring, and collaboration with PCPs and specialists. Regular follow-up with a dermatologist and PCP is strongly recommended for patients with psoriasis given the systemic nature of the disease. The 2019 AAD-NPF recommendations provide important information for dermatologists to coordinate care for complicated psoriasis cases, but clinical judgment is paramount when making medical decisions. The consideration of comorbidities is critical for developing a comprehensive treatment approach, and this approach will lead to better health outcomes and improved QOL for patients with psoriasis.

Biologics have transformed the management of moderate to severe psoriasis. There currently are 11 biologics approved by the US Food and Drug Administration (Table) for psoriasis treatment that have been affirmed by various clinical studies. This article provides dosing initiation, maintenance information, and updated clinical data using phase 3 studies (N=8) published between May 2020 and February 2021. Generic names of the 11 biologics were searched separately in the PubMed database within the specified date range. Subsequent results were reviewed by title and selected for phase 3 and 4 trials. Clinical data in this review focus on reducing patient disease burden by allocating a biologic best fit for each patient’s individual health profile.

IL-17A Inhibitors Update

Secukinumab is safe and efficacious for skin clearance in the presence of comorbidities and can be used for improving plaque psoriasis and palmoplantar pustular psoriasis. An extension of a phase 3 randomized controlled trial (RCT)—2PRECISE—evaluated the efficacy and safety of secukinumab dosing at 300 mg (n=79) and 150 mg (n=80) in adults with moderate to severe palmoplantar pustular psoriasis (palmoplantar psoriasis area and severity index [PPPASI] score ≥12 and dermatology life quality index [DLQI] ≥10) over 148 weeks.¹ Extension patients were included from the 52-week 2PRECISE study per the investigator’s judgement of a meaningful clinical response (exact criteria not described). All treatment groups demonstrated a mean (SD) PPPASI of 22.7 (9.5) by the extension trial’s start. Results affirmed that clinical response waned after week 148 in all groups excluding placebo/secukinumab 150 mg, which maintained a mean (SD) PPPASI of 22.7 (9.5). The most frequent adverse events were nasopharyngitis, pustular psoriasis, headache, and pruritus.¹

Comorbidities do not have a major impact on secukinumab’s efficacy. A post hoc analysis of 4 phase 3 RCTs—ERASURE, FIXTURE, FEATURE, and JUNCTURE—gathered data from adult patients (N=2401) to assess baseline comorbidities with efficacy and safety of secukinumab vs etanercept after 12 weeks of treatment.² Sixty-one percent (n=1469) had at least 1 comorbidity, most frequently obesity, hypertension, psoriatic arthritis, hyperlipidemia, or diabetes mellitus. All patient groups had a greater likelihood of a psoriasis area and severity index (PASI) response with any dose of secukinumab vs patients with comorbidities who were taking etanercept or placebo (P<.05) at week 12. All groups had a greater likelihood of achieving investigator global assessment scores of 0/1 (clear/almost clear) vs patients with comorbidities taking etanercept or placebo (P<.05). Baseline comorbidities did not significantly affect treatment response, except obesity, which was associated with decreased probability of achieving all PASI and investigator global assessment (P<.01) responses. Secukinumab-treated patients with and without comorbidities had equivalent likelihood of treatment-emergent adverse events (TEAEs).²

Brodalumab is an effective biologic that has shown long-term safety with continuous administration. Continuous brodalumab and brodalumab after placebo demonstrated impactful skin clearance after 120 weeks in AMAGINE-1, a phase 3 RCT involving adults (N=442) with moderate to severe plaque psoriasis.³ Patients randomized to brodalumab 210 mg (n=222) or placebo (n=220) were rerandomized according to initial treatment response. In patients switching from brodalumab to placebo at week 12, 55% and 94% achieved PASI 75 at week 20 and week 120, respectively, and 75% reached PASI 100 at week 120. Of patients with static physician global assessment (sPGA) scores of 0/1 (clear/almost clear) at week 12 who were rerandomized to brodalumab, 96% and 80% (using observed data) achieved PASI 75 and PASI 100, respectively. Mean (SD) time to return of skin disease following withdrawal of brodalumab was 74.7 (50.5) days. Treatment-emergent adverse events included headaches, arthralgia, diarrhea, and nausea. Suicidal ideation was rare (this study had 1 completed suicide), and authors cited that no causal association has been made between brodalumab and suicidality. Brodalumab also demonstrated favorable treatment response in patients who underwent a lapse in treatment, offering real-world value, as intermittent treatment administration can occur because of personal or financial reasons.³

Ixekizumab is associated with more rapid skin clearance, better resolution of nail psoriasis, and superior improvement in quality-of-life measures when compared with guselkumab. The phase 3 study IXORA-R compared skin and nail clearance as well as patient-reported outcomes over 24 weeks with ixekizumab 80 mg (n=520) vs guselkumab 100 mg (n=507) in adults with moderate to severe plaque psoriasis.⁴ Ixekizumab (50%) was shown to be no worse than guselkumab (52%; difference, –2.3%) using a noninferiority test (noninferiority margin of –11.4%). The treatments exhibited similar efficacy, with no significant difference in proportion of patients reaching PASI 100 (P=.41). Ixekizumab patients tended to have skin clearance sooner than guselkumab patients, reaching PASI 50/75/90 and PASI 100 in a median time that was 2 weeks and 7.5 weeks earlier, respectively. More ixekizumab patients (52%) achieved clear nails vs guselkumab patients (31%; P=.007). Ixekizumab patients reported greater satisfaction with their skin disease affecting quality of life (DLQI), with more DLQI 0/1 (no effect at all on patient’s life) scores and being itch free (P<.05). Ixekizumab was associated with significantly more days of complete skin clearance (PASI 100) vs guselkumab (55.6 days vs 42.2 days; P<.001). Although an upper respiratory tract infection was the most common TEAE, the proportion of TEAEs was similar between treatments.⁴

IL-23 Inhibitors Update

Tildrakizumab has similar long-term skin clearance efficacy and safety in patients with psoriasis with and without comorbid metabolic syndrome (MetS). A post hoc analysis of 2 phase 2 RCTs (reSURFACE 1/2) involving adults (N=338 and N=307) with moderate to severe plaque psoriasis assessed long-term efficacy (3 years), drug survival, and safety for 5 years of continuous tildrakizumab 100 mg and 200 mg in adults with comorbid MetS.⁵ Although no difference in efficacy was concluded, greater body mass index of the MetS population was shown to be associated with lower biologic efficacy compared to the general population. The proportion of patients who achieved PASI 75 at week 52 was comparable in patients with MetS and patients without MetS (tildrakizumab 100 mg, 85% and 86% vs 86% and 94% for reSURFACE 1/2, respectively; tildrakizumab 200 mg, 76% and 87% vs 76% and 87% for reSURFACE 1/2, respectively).⁵

Tildrakizumab also demonstrated efficacy and safety for up to 5 years in 2 other phase 3 RCTs with no dose-related differences in frequency of injections and malignancies. Tildrakizumab 100 mg is the recommended dose. The 200-mg dose can be utilized in patients with a high burden of disease and disability. reSURFACE 1 and reSURFACE 2 involved adults with chronic moderate to severe plaque psoriasis randomized to tildrakizumab 100 mg, 200 mg, or placebo with the option of long-term extension to week 244 if patients reached 50% or greater improvement from baseline PASI score.⁶ Patients in reSURFACE 2 also were randomized to etanercept 50 mg with partial responders and nonresponders at week 28 switching to tildrakizumab 200 mg until week 244. Extension results showed PASI 75 achievement in 88.7% (95% CI, 84.6%-92.1%) of patients taking tildrakizumab 100 mg (n=235), 92.5% (95% CI, 88.1%-95.7%) of patients taking tildrakizumab 200 mg (n=176), and 81.3% (95% CI, 72.6%-88.2%) of patients taking etanercept/partial nonresponders (n=85). The most common TEAE was nasopharyngitis (10.5/100 patient-years for tildrakizumab 100 mg and 10.7/100 patient-years for tildrakizumab 200 mg). The frequency of severe infections (eg, diverticulitis, pneumonia, cellulitis, appendicitis) was 1.2 per 100 patient-years for tildrakizumab 100 mg and 1.3 per 100 patient-years for tildrakizumab 200 mg.⁶

Risankizumab and tildrakizumab require the lowest number of injections, thereby providing sustainable skin clearance with a convenient injection dosing schedule for patients. Risankizumab efficacy (8.2% with inferiority margin of 12%) was noninferior to secukinumab when assessing the proportion of PASI 90 responders at week 16 (after 2 doses of risankizumab vs 7 doses of secukinumab).⁷ IMMerge, an international phase 3 RCT, involved adults (N=327) with moderate to severe plaque psoriasis to compare the safety and efficacy of risankizumab 150 mg (n=164) vs secukinumab 300 mg (n=163) up to 52 weeks. A greater proportion of the risankizumab arm (86.6%) achieved PASI 90 in 52 weeks compared to the secukinumab arm (57.1%). Superior skin clearance (PASI 90) at week 52 was achieved after 5 doses with risankizumab vs 16 doses of secukinumab. Risankizumab TEAEs were nasopharyngitis, upper respiratory tract infection, headache, arthralgia, diarrhea, and bronchitis.⁷

Continuous risankizumab treatment shows substantially stronger skin clearing performance compared with intermittent treatment following drug withdrawal, demonstrating that treatment gaps minimize therapeutic response. IMMhance, an international phase 3 RCT involving adults (N=507) with moderate to severe plaque psoriasis, evaluated the safety and efficacy with risankizumab 150 mg after 52 weeks and 104 weeks.⁸ Part A randomized patients to risankizumab 150 mg (n=407) or placebo (n=100). Part B rerandomized patients at week 28 to continue risankizumab 150 mg or placebo (designated as withdrawal of treatment; later re-treated with risankizumab 150 mg if patients had sPGA ≥3). At week 52, significantly more patients reached sPGA score of 0/1 with risankizumab/risankizumab (n=97 [87.4%]) vs risankizumab/placebo (n=138 [61.3%]; P<.001). At week 104, significantly more patients reached an sPGA score of 0/1 with risankizumab/risankizumab (n=90 [81.1%]) vs risankizumab/placebo (n=16 [7.1%]; P<.001). Risankizumab exhibited longevity following withdrawal, as median time to loss of response and relapse was 42 weeks (sPGA ≥3). The extent of TEAEs was similar between risankizumab and placebo and included nasopharyngitis, upper respiratory tract infection, headache, and back pain.⁸

Final Thoughts

Biologics for psoriasis help produce intended results for skin disease clearance and are tools for precision medicine. Recent data demonstrate safe, durable, and continuous efficacy with biologics, which offer patients a better chance of treatment success. This guide may serve as a quick reference for biologic selection with special consideration of individual disease characteristics and comorbidities.

Biologics have transformed the management of moderate to severe psoriasis. There currently are 11 biologics approved by the US Food and Drug Administration (Table) for psoriasis treatment that have been affirmed by various clinical studies. This article provides dosing initiation, maintenance information, and updated clinical data using phase 3 studies (N=8) published between May 2020 and February 2021. Generic names of the 11 biologics were searched separately in the PubMed database within the specified date range. Subsequent results were reviewed by title and selected for phase 3 and 4 trials. Clinical data in this review focus on reducing patient disease burden by allocating a biologic best fit for each patient’s individual health profile.

IL-17A Inhibitors Update

Secukinumab is safe and efficacious for skin clearance in the presence of comorbidities and can be used for improving plaque psoriasis and palmoplantar pustular psoriasis. An extension of a phase 3 randomized controlled trial (RCT)—2PRECISE—evaluated the efficacy and safety of secukinumab dosing at 300 mg (n=79) and 150 mg (n=80) in adults with moderate to severe palmoplantar pustular psoriasis (palmoplantar psoriasis area and severity index [PPPASI] score ≥12 and dermatology life quality index [DLQI] ≥10) over 148 weeks.¹ Extension patients were included from the 52-week 2PRECISE study per the investigator’s judgement of a meaningful clinical response (exact criteria not described). All treatment groups demonstrated a mean (SD) PPPASI of 22.7 (9.5) by the extension trial’s start. Results affirmed that clinical response waned after week 148 in all groups excluding placebo/secukinumab 150 mg, which maintained a mean (SD) PPPASI of 22.7 (9.5). The most frequent adverse events were nasopharyngitis, pustular psoriasis, headache, and pruritus.¹

Comorbidities do not have a major impact on secukinumab’s efficacy. A post hoc analysis of 4 phase 3 RCTs—ERASURE, FIXTURE, FEATURE, and JUNCTURE—gathered data from adult patients (N=2401) to assess baseline comorbidities with efficacy and safety of secukinumab vs etanercept after 12 weeks of treatment.² Sixty-one percent (n=1469) had at least 1 comorbidity, most frequently obesity, hypertension, psoriatic arthritis, hyperlipidemia, or diabetes mellitus. All patient groups had a greater likelihood of a psoriasis area and severity index (PASI) response with any dose of secukinumab vs patients with comorbidities who were taking etanercept or placebo (P<.05) at week 12. All groups had a greater likelihood of achieving investigator global assessment scores of 0/1 (clear/almost clear) vs patients with comorbidities taking etanercept or placebo (P<.05). Baseline comorbidities did not significantly affect treatment response, except obesity, which was associated with decreased probability of achieving all PASI and investigator global assessment (P<.01) responses. Secukinumab-treated patients with and without comorbidities had equivalent likelihood of treatment-emergent adverse events (TEAEs).²

Brodalumab is an effective biologic that has shown long-term safety with continuous administration. Continuous brodalumab and brodalumab after placebo demonstrated impactful skin clearance after 120 weeks in AMAGINE-1, a phase 3 RCT involving adults (N=442) with moderate to severe plaque psoriasis.³ Patients randomized to brodalumab 210 mg (n=222) or placebo (n=220) were rerandomized according to initial treatment response. In patients switching from brodalumab to placebo at week 12, 55% and 94% achieved PASI 75 at week 20 and week 120, respectively, and 75% reached PASI 100 at week 120. Of patients with static physician global assessment (sPGA) scores of 0/1 (clear/almost clear) at week 12 who were rerandomized to brodalumab, 96% and 80% (using observed data) achieved PASI 75 and PASI 100, respectively. Mean (SD) time to return of skin disease following withdrawal of brodalumab was 74.7 (50.5) days. Treatment-emergent adverse events included headaches, arthralgia, diarrhea, and nausea. Suicidal ideation was rare (this study had 1 completed suicide), and authors cited that no causal association has been made between brodalumab and suicidality. Brodalumab also demonstrated favorable treatment response in patients who underwent a lapse in treatment, offering real-world value, as intermittent treatment administration can occur because of personal or financial reasons.³

Ixekizumab is associated with more rapid skin clearance, better resolution of nail psoriasis, and superior improvement in quality-of-life measures when compared with guselkumab. The phase 3 study IXORA-R compared skin and nail clearance as well as patient-reported outcomes over 24 weeks with ixekizumab 80 mg (n=520) vs guselkumab 100 mg (n=507) in adults with moderate to severe plaque psoriasis.⁴ Ixekizumab (50%) was shown to be no worse than guselkumab (52%; difference, –2.3%) using a noninferiority test (noninferiority margin of –11.4%). The treatments exhibited similar efficacy, with no significant difference in proportion of patients reaching PASI 100 (P=.41). Ixekizumab patients tended to have skin clearance sooner than guselkumab patients, reaching PASI 50/75/90 and PASI 100 in a median time that was 2 weeks and 7.5 weeks earlier, respectively. More ixekizumab patients (52%) achieved clear nails vs guselkumab patients (31%; P=.007). Ixekizumab patients reported greater satisfaction with their skin disease affecting quality of life (DLQI), with more DLQI 0/1 (no effect at all on patient’s life) scores and being itch free (P<.05). Ixekizumab was associated with significantly more days of complete skin clearance (PASI 100) vs guselkumab (55.6 days vs 42.2 days; P<.001). Although an upper respiratory tract infection was the most common TEAE, the proportion of TEAEs was similar between treatments.⁴

IL-23 Inhibitors Update

Tildrakizumab has similar long-term skin clearance efficacy and safety in patients with psoriasis with and without comorbid metabolic syndrome (MetS). A post hoc analysis of 2 phase 2 RCTs (reSURFACE 1/2) involving adults (N=338 and N=307) with moderate to severe plaque psoriasis assessed long-term efficacy (3 years), drug survival, and safety for 5 years of continuous tildrakizumab 100 mg and 200 mg in adults with comorbid MetS.⁵ Although no difference in efficacy was concluded, greater body mass index of the MetS population was shown to be associated with lower biologic efficacy compared to the general population. The proportion of patients who achieved PASI 75 at week 52 was comparable in patients with MetS and patients without MetS (tildrakizumab 100 mg, 85% and 86% vs 86% and 94% for reSURFACE 1/2, respectively; tildrakizumab 200 mg, 76% and 87% vs 76% and 87% for reSURFACE 1/2, respectively).⁵

Tildrakizumab also demonstrated efficacy and safety for up to 5 years in 2 other phase 3 RCTs with no dose-related differences in frequency of injections and malignancies. Tildrakizumab 100 mg is the recommended dose. The 200-mg dose can be utilized in patients with a high burden of disease and disability. reSURFACE 1 and reSURFACE 2 involved adults with chronic moderate to severe plaque psoriasis randomized to tildrakizumab 100 mg, 200 mg, or placebo with the option of long-term extension to week 244 if patients reached 50% or greater improvement from baseline PASI score.⁶ Patients in reSURFACE 2 also were randomized to etanercept 50 mg with partial responders and nonresponders at week 28 switching to tildrakizumab 200 mg until week 244. Extension results showed PASI 75 achievement in 88.7% (95% CI, 84.6%-92.1%) of patients taking tildrakizumab 100 mg (n=235), 92.5% (95% CI, 88.1%-95.7%) of patients taking tildrakizumab 200 mg (n=176), and 81.3% (95% CI, 72.6%-88.2%) of patients taking etanercept/partial nonresponders (n=85). The most common TEAE was nasopharyngitis (10.5/100 patient-years for tildrakizumab 100 mg and 10.7/100 patient-years for tildrakizumab 200 mg). The frequency of severe infections (eg, diverticulitis, pneumonia, cellulitis, appendicitis) was 1.2 per 100 patient-years for tildrakizumab 100 mg and 1.3 per 100 patient-years for tildrakizumab 200 mg.⁶

Risankizumab and tildrakizumab require the lowest number of injections, thereby providing sustainable skin clearance with a convenient injection dosing schedule for patients. Risankizumab efficacy (8.2% with inferiority margin of 12%) was noninferior to secukinumab when assessing the proportion of PASI 90 responders at week 16 (after 2 doses of risankizumab vs 7 doses of secukinumab).⁷ IMMerge, an international phase 3 RCT, involved adults (N=327) with moderate to severe plaque psoriasis to compare the safety and efficacy of risankizumab 150 mg (n=164) vs secukinumab 300 mg (n=163) up to 52 weeks. A greater proportion of the risankizumab arm (86.6%) achieved PASI 90 in 52 weeks compared to the secukinumab arm (57.1%). Superior skin clearance (PASI 90) at week 52 was achieved after 5 doses with risankizumab vs 16 doses of secukinumab. Risankizumab TEAEs were nasopharyngitis, upper respiratory tract infection, headache, arthralgia, diarrhea, and bronchitis.⁷

Continuous risankizumab treatment shows substantially stronger skin clearing performance compared with intermittent treatment following drug withdrawal, demonstrating that treatment gaps minimize therapeutic response. IMMhance, an international phase 3 RCT involving adults (N=507) with moderate to severe plaque psoriasis, evaluated the safety and efficacy with risankizumab 150 mg after 52 weeks and 104 weeks.⁸ Part A randomized patients to risankizumab 150 mg (n=407) or placebo (n=100). Part B rerandomized patients at week 28 to continue risankizumab 150 mg or placebo (designated as withdrawal of treatment; later re-treated with risankizumab 150 mg if patients had sPGA ≥3). At week 52, significantly more patients reached sPGA score of 0/1 with risankizumab/risankizumab (n=97 [87.4%]) vs risankizumab/placebo (n=138 [61.3%]; P<.001). At week 104, significantly more patients reached an sPGA score of 0/1 with risankizumab/risankizumab (n=90 [81.1%]) vs risankizumab/placebo (n=16 [7.1%]; P<.001). Risankizumab exhibited longevity following withdrawal, as median time to loss of response and relapse was 42 weeks (sPGA ≥3). The extent of TEAEs was similar between risankizumab and placebo and included nasopharyngitis, upper respiratory tract infection, headache, and back pain.⁸

Final Thoughts

Biologics for psoriasis help produce intended results for skin disease clearance and are tools for precision medicine. Recent data demonstrate safe, durable, and continuous efficacy with biologics, which offer patients a better chance of treatment success. This guide may serve as a quick reference for biologic selection with special consideration of individual disease characteristics and comorbidities.

Biologics have transformed the management of moderate to severe psoriasis. There currently are 11 biologics approved by the US Food and Drug Administration (Table) for psoriasis treatment that have been affirmed by various clinical studies. This article provides dosing initiation, maintenance information, and updated clinical data using phase 3 studies (N=8) published between May 2020 and February 2021. Generic names of the 11 biologics were searched separately in the PubMed database within the specified date range. Subsequent results were reviewed by title and selected for phase 3 and 4 trials. Clinical data in this review focus on reducing patient disease burden by allocating a biologic best fit for each patient’s individual health profile.

IL-17A Inhibitors Update

Secukinumab is safe and efficacious for skin clearance in the presence of comorbidities and can be used for improving plaque psoriasis and palmoplantar pustular psoriasis. An extension of a phase 3 randomized controlled trial (RCT)—2PRECISE—evaluated the efficacy and safety of secukinumab dosing at 300 mg (n=79) and 150 mg (n=80) in adults with moderate to severe palmoplantar pustular psoriasis (palmoplantar psoriasis area and severity index [PPPASI] score ≥12 and dermatology life quality index [DLQI] ≥10) over 148 weeks.¹ Extension patients were included from the 52-week 2PRECISE study per the investigator’s judgement of a meaningful clinical response (exact criteria not described). All treatment groups demonstrated a mean (SD) PPPASI of 22.7 (9.5) by the extension trial’s start. Results affirmed that clinical response waned after week 148 in all groups excluding placebo/secukinumab 150 mg, which maintained a mean (SD) PPPASI of 22.7 (9.5). The most frequent adverse events were nasopharyngitis, pustular psoriasis, headache, and pruritus.¹

Comorbidities do not have a major impact on secukinumab’s efficacy. A post hoc analysis of 4 phase 3 RCTs—ERASURE, FIXTURE, FEATURE, and JUNCTURE—gathered data from adult patients (N=2401) to assess baseline comorbidities with efficacy and safety of secukinumab vs etanercept after 12 weeks of treatment.² Sixty-one percent (n=1469) had at least 1 comorbidity, most frequently obesity, hypertension, psoriatic arthritis, hyperlipidemia, or diabetes mellitus. All patient groups had a greater likelihood of a psoriasis area and severity index (PASI) response with any dose of secukinumab vs patients with comorbidities who were taking etanercept or placebo (P<.05) at week 12. All groups had a greater likelihood of achieving investigator global assessment scores of 0/1 (clear/almost clear) vs patients with comorbidities taking etanercept or placebo (P<.05). Baseline comorbidities did not significantly affect treatment response, except obesity, which was associated with decreased probability of achieving all PASI and investigator global assessment (P<.01) responses. Secukinumab-treated patients with and without comorbidities had equivalent likelihood of treatment-emergent adverse events (TEAEs).²

Brodalumab is an effective biologic that has shown long-term safety with continuous administration. Continuous brodalumab and brodalumab after placebo demonstrated impactful skin clearance after 120 weeks in AMAGINE-1, a phase 3 RCT involving adults (N=442) with moderate to severe plaque psoriasis.³ Patients randomized to brodalumab 210 mg (n=222) or placebo (n=220) were rerandomized according to initial treatment response. In patients switching from brodalumab to placebo at week 12, 55% and 94% achieved PASI 75 at week 20 and week 120, respectively, and 75% reached PASI 100 at week 120. Of patients with static physician global assessment (sPGA) scores of 0/1 (clear/almost clear) at week 12 who were rerandomized to brodalumab, 96% and 80% (using observed data) achieved PASI 75 and PASI 100, respectively. Mean (SD) time to return of skin disease following withdrawal of brodalumab was 74.7 (50.5) days. Treatment-emergent adverse events included headaches, arthralgia, diarrhea, and nausea. Suicidal ideation was rare (this study had 1 completed suicide), and authors cited that no causal association has been made between brodalumab and suicidality. Brodalumab also demonstrated favorable treatment response in patients who underwent a lapse in treatment, offering real-world value, as intermittent treatment administration can occur because of personal or financial reasons.³

Ixekizumab is associated with more rapid skin clearance, better resolution of nail psoriasis, and superior improvement in quality-of-life measures when compared with guselkumab. The phase 3 study IXORA-R compared skin and nail clearance as well as patient-reported outcomes over 24 weeks with ixekizumab 80 mg (n=520) vs guselkumab 100 mg (n=507) in adults with moderate to severe plaque psoriasis.⁴ Ixekizumab (50%) was shown to be no worse than guselkumab (52%; difference, –2.3%) using a noninferiority test (noninferiority margin of –11.4%). The treatments exhibited similar efficacy, with no significant difference in proportion of patients reaching PASI 100 (P=.41). Ixekizumab patients tended to have skin clearance sooner than guselkumab patients, reaching PASI 50/75/90 and PASI 100 in a median time that was 2 weeks and 7.5 weeks earlier, respectively. More ixekizumab patients (52%) achieved clear nails vs guselkumab patients (31%; P=.007). Ixekizumab patients reported greater satisfaction with their skin disease affecting quality of life (DLQI), with more DLQI 0/1 (no effect at all on patient’s life) scores and being itch free (P<.05). Ixekizumab was associated with significantly more days of complete skin clearance (PASI 100) vs guselkumab (55.6 days vs 42.2 days; P<.001). Although an upper respiratory tract infection was the most common TEAE, the proportion of TEAEs was similar between treatments.⁴

IL-23 Inhibitors Update

Tildrakizumab has similar long-term skin clearance efficacy and safety in patients with psoriasis with and without comorbid metabolic syndrome (MetS). A post hoc analysis of 2 phase 2 RCTs (reSURFACE 1/2) involving adults (N=338 and N=307) with moderate to severe plaque psoriasis assessed long-term efficacy (3 years), drug survival, and safety for 5 years of continuous tildrakizumab 100 mg and 200 mg in adults with comorbid MetS.⁵ Although no difference in efficacy was concluded, greater body mass index of the MetS population was shown to be associated with lower biologic efficacy compared to the general population. The proportion of patients who achieved PASI 75 at week 52 was comparable in patients with MetS and patients without MetS (tildrakizumab 100 mg, 85% and 86% vs 86% and 94% for reSURFACE 1/2, respectively; tildrakizumab 200 mg, 76% and 87% vs 76% and 87% for reSURFACE 1/2, respectively).⁵

Tildrakizumab also demonstrated efficacy and safety for up to 5 years in 2 other phase 3 RCTs with no dose-related differences in frequency of injections and malignancies. Tildrakizumab 100 mg is the recommended dose. The 200-mg dose can be utilized in patients with a high burden of disease and disability. reSURFACE 1 and reSURFACE 2 involved adults with chronic moderate to severe plaque psoriasis randomized to tildrakizumab 100 mg, 200 mg, or placebo with the option of long-term extension to week 244 if patients reached 50% or greater improvement from baseline PASI score.⁶ Patients in reSURFACE 2 also were randomized to etanercept 50 mg with partial responders and nonresponders at week 28 switching to tildrakizumab 200 mg until week 244. Extension results showed PASI 75 achievement in 88.7% (95% CI, 84.6%-92.1%) of patients taking tildrakizumab 100 mg (n=235), 92.5% (95% CI, 88.1%-95.7%) of patients taking tildrakizumab 200 mg (n=176), and 81.3% (95% CI, 72.6%-88.2%) of patients taking etanercept/partial nonresponders (n=85). The most common TEAE was nasopharyngitis (10.5/100 patient-years for tildrakizumab 100 mg and 10.7/100 patient-years for tildrakizumab 200 mg). The frequency of severe infections (eg, diverticulitis, pneumonia, cellulitis, appendicitis) was 1.2 per 100 patient-years for tildrakizumab 100 mg and 1.3 per 100 patient-years for tildrakizumab 200 mg.⁶

Risankizumab and tildrakizumab require the lowest number of injections, thereby providing sustainable skin clearance with a convenient injection dosing schedule for patients. Risankizumab efficacy (8.2% with inferiority margin of 12%) was noninferior to secukinumab when assessing the proportion of PASI 90 responders at week 16 (after 2 doses of risankizumab vs 7 doses of secukinumab).⁷ IMMerge, an international phase 3 RCT, involved adults (N=327) with moderate to severe plaque psoriasis to compare the safety and efficacy of risankizumab 150 mg (n=164) vs secukinumab 300 mg (n=163) up to 52 weeks. A greater proportion of the risankizumab arm (86.6%) achieved PASI 90 in 52 weeks compared to the secukinumab arm (57.1%). Superior skin clearance (PASI 90) at week 52 was achieved after 5 doses with risankizumab vs 16 doses of secukinumab. Risankizumab TEAEs were nasopharyngitis, upper respiratory tract infection, headache, arthralgia, diarrhea, and bronchitis.⁷

Continuous risankizumab treatment shows substantially stronger skin clearing performance compared with intermittent treatment following drug withdrawal, demonstrating that treatment gaps minimize therapeutic response. IMMhance, an international phase 3 RCT involving adults (N=507) with moderate to severe plaque psoriasis, evaluated the safety and efficacy with risankizumab 150 mg after 52 weeks and 104 weeks.⁸ Part A randomized patients to risankizumab 150 mg (n=407) or placebo (n=100). Part B rerandomized patients at week 28 to continue risankizumab 150 mg or placebo (designated as withdrawal of treatment; later re-treated with risankizumab 150 mg if patients had sPGA ≥3). At week 52, significantly more patients reached sPGA score of 0/1 with risankizumab/risankizumab (n=97 [87.4%]) vs risankizumab/placebo (n=138 [61.3%]; P<.001). At week 104, significantly more patients reached an sPGA score of 0/1 with risankizumab/risankizumab (n=90 [81.1%]) vs risankizumab/placebo (n=16 [7.1%]; P<.001). Risankizumab exhibited longevity following withdrawal, as median time to loss of response and relapse was 42 weeks (sPGA ≥3). The extent of TEAEs was similar between risankizumab and placebo and included nasopharyngitis, upper respiratory tract infection, headache, and back pain.⁸

Final Thoughts

Biologics for psoriasis help produce intended results for skin disease clearance and are tools for precision medicine. Recent data demonstrate safe, durable, and continuous efficacy with biologics, which offer patients a better chance of treatment success. This guide may serve as a quick reference for biologic selection with special consideration of individual disease characteristics and comorbidities.

Office-based phototherapy practices have closed or are operating below capacity because of the coronavirus disease 2019 (COVID-19) pandemic.¹ Social distancing measures to reduce virus transmission are a significant driving factor.^1-3 In the age of biologics, other options requiring fewer patient visits are available, such as UVB phototherapy. UV phototherapy is considered first line when more than 10% of the body surface area is affected.⁴ Although phototherapy often is performed in the office, it also may be delivered at home.² Home-based phototherapy is safe, effective, and similar in cost to office-based phototherapy.⁴ Currently, there are limited COVID-19–specific guidelines for home-based phototherapy.

The risks and sequelae of COVID-19 are still being investigated, with cases varying by location. As such, local and national public health recommendations are evolving. Dermatologists must make individualized decisions about practice services, as local restrictions differ. As office-based phototherapy services may struggle to implement mitigation strategies, home-based phototherapy is an increasingly viable treatment option.^1,4,5 Patient benefits of home therapy include improved treatment compliance; greater patient satisfaction; reduced travel/waiting time; and reduced long-term cost, including co-pays, depending on insurance coverage.^2,4

We aim to provide recommendations on home-based phototherapy during the pandemic. Throughout the decision-making process, careful consideration of safety, risks, benefits, and treatment options for physicians, staff, and patients will be vital to the successful implementation of home-based phototherapy. Our recommendations are based on maximizing benefits and minimizing risks.

Considerations for Physicians

Physicians should take the following steps when assessing if home phototherapy is an option for each patient.^1,2,4

• Determine patient eligibility for phototherapy treatment if currently not on phototherapy

• Carefully review patient and provider requirements for home phototherapy supplier

• Review patient history of treatment compliance

• Determine insurance coverage and consider exclusion criteria

• Review prior treatments

• Provide education on side effects

• Provide education on signs of adequate treatment response

• Indicate the type of UV light and unit on the prescription

• Consider whether the patient is in the maintenance or initiation phase when providing recommendations

• Work with the supplier if the light therapy unit is denied by submitting an appeal or prescribing a different unit

• Follow up with telemedicine to assess treatment effectiveness and monitor for adverse effects

Considerations for Patients

Counsel patients to weigh the risks and benefits of home phototherapy prescription and usage.^1,2,4

• Evaluate cost

• Carefully review patient and provider requirements for home phototherapy supplier

• Ensure a complete understanding of treatment schedule

• Properly utilize protective equipment (eg, genital shields for men, eye shields for all)

• Avoid sharing phototherapy units with household members

• Disinfect and maintain units

• Maintain proper ventilation of spaces

• Maintain treatment log

• Attend follow-up

Treatment Alternatives

For patients with severe psoriasis, there are alternative treatments to office and home phototherapy. Biologics, immunosuppressive therapies, and other treatment options may be considered on a case-by-case basis.^3,4,6 Currently, recommendations for the risk of COVID-19 with biologics or systemic immunosuppressive therapies remains inconsistent and should be carefully considered when providing alternative treatments.^7-11

Final Thoughts

As restrictions are lifted according to local public health measures, prepandemic office phototherapy practices may resume operations. Home phototherapy is a practical and effective alternative for treatment of psoriasis when access to the office setting is limited.

Office-based phototherapy practices have closed or are operating below capacity because of the coronavirus disease 2019 (COVID-19) pandemic.¹ Social distancing measures to reduce virus transmission are a significant driving factor.^1-3 In the age of biologics, other options requiring fewer patient visits are available, such as UVB phototherapy. UV phototherapy is considered first line when more than 10% of the body surface area is affected.⁴ Although phototherapy often is performed in the office, it also may be delivered at home.² Home-based phototherapy is safe, effective, and similar in cost to office-based phototherapy.⁴ Currently, there are limited COVID-19–specific guidelines for home-based phototherapy.

The risks and sequelae of COVID-19 are still being investigated, with cases varying by location. As such, local and national public health recommendations are evolving. Dermatologists must make individualized decisions about practice services, as local restrictions differ. As office-based phototherapy services may struggle to implement mitigation strategies, home-based phototherapy is an increasingly viable treatment option.^1,4,5 Patient benefits of home therapy include improved treatment compliance; greater patient satisfaction; reduced travel/waiting time; and reduced long-term cost, including co-pays, depending on insurance coverage.^2,4

We aim to provide recommendations on home-based phototherapy during the pandemic. Throughout the decision-making process, careful consideration of safety, risks, benefits, and treatment options for physicians, staff, and patients will be vital to the successful implementation of home-based phototherapy. Our recommendations are based on maximizing benefits and minimizing risks.

Considerations for Physicians

Physicians should take the following steps when assessing if home phototherapy is an option for each patient.^1,2,4

• Determine patient eligibility for phototherapy treatment if currently not on phototherapy

• Carefully review patient and provider requirements for home phototherapy supplier

• Review patient history of treatment compliance

• Determine insurance coverage and consider exclusion criteria

• Review prior treatments

• Provide education on side effects

• Provide education on signs of adequate treatment response

• Indicate the type of UV light and unit on the prescription

• Consider whether the patient is in the maintenance or initiation phase when providing recommendations

• Work with the supplier if the light therapy unit is denied by submitting an appeal or prescribing a different unit

• Follow up with telemedicine to assess treatment effectiveness and monitor for adverse effects

Considerations for Patients

Counsel patients to weigh the risks and benefits of home phototherapy prescription and usage.^1,2,4

• Evaluate cost

• Carefully review patient and provider requirements for home phototherapy supplier

• Ensure a complete understanding of treatment schedule

• Properly utilize protective equipment (eg, genital shields for men, eye shields for all)

• Avoid sharing phototherapy units with household members

• Disinfect and maintain units

• Maintain proper ventilation of spaces

• Maintain treatment log

• Attend follow-up

Treatment Alternatives

For patients with severe psoriasis, there are alternative treatments to office and home phototherapy. Biologics, immunosuppressive therapies, and other treatment options may be considered on a case-by-case basis.^3,4,6 Currently, recommendations for the risk of COVID-19 with biologics or systemic immunosuppressive therapies remains inconsistent and should be carefully considered when providing alternative treatments.^7-11

Final Thoughts

As restrictions are lifted according to local public health measures, prepandemic office phototherapy practices may resume operations. Home phototherapy is a practical and effective alternative for treatment of psoriasis when access to the office setting is limited.

Office-based phototherapy practices have closed or are operating below capacity because of the coronavirus disease 2019 (COVID-19) pandemic.¹ Social distancing measures to reduce virus transmission are a significant driving factor.^1-3 In the age of biologics, other options requiring fewer patient visits are available, such as UVB phototherapy. UV phototherapy is considered first line when more than 10% of the body surface area is affected.⁴ Although phototherapy often is performed in the office, it also may be delivered at home.² Home-based phototherapy is safe, effective, and similar in cost to office-based phototherapy.⁴ Currently, there are limited COVID-19–specific guidelines for home-based phototherapy.

The risks and sequelae of COVID-19 are still being investigated, with cases varying by location. As such, local and national public health recommendations are evolving. Dermatologists must make individualized decisions about practice services, as local restrictions differ. As office-based phototherapy services may struggle to implement mitigation strategies, home-based phototherapy is an increasingly viable treatment option.^1,4,5 Patient benefits of home therapy include improved treatment compliance; greater patient satisfaction; reduced travel/waiting time; and reduced long-term cost, including co-pays, depending on insurance coverage.^2,4

We aim to provide recommendations on home-based phototherapy during the pandemic. Throughout the decision-making process, careful consideration of safety, risks, benefits, and treatment options for physicians, staff, and patients will be vital to the successful implementation of home-based phototherapy. Our recommendations are based on maximizing benefits and minimizing risks.

Considerations for Physicians

Physicians should take the following steps when assessing if home phototherapy is an option for each patient.^1,2,4

• Determine patient eligibility for phototherapy treatment if currently not on phototherapy

• Carefully review patient and provider requirements for home phototherapy supplier

• Review patient history of treatment compliance

• Determine insurance coverage and consider exclusion criteria

• Review prior treatments

• Provide education on side effects

• Provide education on signs of adequate treatment response

• Indicate the type of UV light and unit on the prescription

• Consider whether the patient is in the maintenance or initiation phase when providing recommendations

• Work with the supplier if the light therapy unit is denied by submitting an appeal or prescribing a different unit

• Follow up with telemedicine to assess treatment effectiveness and monitor for adverse effects

Considerations for Patients

Counsel patients to weigh the risks and benefits of home phototherapy prescription and usage.^1,2,4

• Evaluate cost

• Carefully review patient and provider requirements for home phototherapy supplier

• Ensure a complete understanding of treatment schedule

• Properly utilize protective equipment (eg, genital shields for men, eye shields for all)

• Avoid sharing phototherapy units with household members

• Disinfect and maintain units

• Maintain proper ventilation of spaces

• Maintain treatment log

• Attend follow-up

Treatment Alternatives

For patients with severe psoriasis, there are alternative treatments to office and home phototherapy. Biologics, immunosuppressive therapies, and other treatment options may be considered on a case-by-case basis.^3,4,6 Currently, recommendations for the risk of COVID-19 with biologics or systemic immunosuppressive therapies remains inconsistent and should be carefully considered when providing alternative treatments.^7-11

Final Thoughts

As restrictions are lifted according to local public health measures, prepandemic office phototherapy practices may resume operations. Home phototherapy is a practical and effective alternative for treatment of psoriasis when access to the office setting is limited.

Psoriasis is a chronic relapsing skin condition characterized by keratinocyte hyperproliferation and a chronic inflammatory cascade. Therefore, controlling inflammatory responses with systemic medications is beneficial in managing psoriatic lesions and their accompanying symptoms, especially in disease inadequately controlled by topicals. Ease of drug administration and treatment availability are benefits that systemic nonbiologic therapies may have over biologic therapies.

In 2020, the American Academy of Dermatology (AAD) and the National Psoriasis Foundation (NPF) published guidelines for managing psoriasis in adults with systemic nonbiologic therapies.¹ Dosing, efficacy, toxicity, drug-related interactions, and contraindications are addressed alongside evidence-based treatment recommendations. This review addresses current recommendations for systemic nonbiologics in psoriasis with a focus on the treatments approved by the US Food and Drug Administration (FDA): acitretin, apremilast, cyclosporine, and methotrexate (eTable). Fumaric acid esters and tofacitinib are FDA approved for psoriatic arthritis but not for plaque psoriasis. Additional long-term safety analyses of tofacitinib for plaque psoriasis were requested by the FDA. Dimethyl fumarate is approved by the European Medicines Agency for treatment of psoriasis and is among the first-line systemic treatments used in Germany.²

Selecting a Systemic Nonbiologic Agent

Methotrexate and apremilast have a strength level A recommendation for treating moderate to severe psoriasis in adults. However, methotrexate is less effective than biologic agents, including adalimumab and infliximab, for cutaneous psoriasis. Methotrexate is believed to improve psoriasis because of its direct immunosuppressive effect and inhibition of lymphoid cell proliferation. It typically is administered orally but can be administered subcutaneously for decreased gastrointestinal (GI) adverse effects. Compliance with close laboratory monitoring and lifestyle modifications, such as contraceptive use (because of teratogenicity) and alcohol cessation (because of the risk of liver damage) are essential in patients using methotrexate.

Apremilast, the most recently FDA-approved oral systemic medication for psoriasis, inhibits phosphodiesterase 4, subsequently decreasing inflammatory responses involving helper T cells T_H1 and T_H17 as well as type 1 interferon pathways. Apremilast is particularly effective in treating psoriasis with scalp and palmoplantar involvement.³ Additionally, it has an encouraging safety profile and is favorable in patients with multiple comorbidities.

Among the 4 oral agents, cyclosporine has the quickest onset of effect and has a strength level A recommendation for treating severe and recalcitrant psoriasis. Because of its high-risk profile, it is recommended for short periods of time, acute flares, or during transitions to safer long-term treatment. Patients with multiple comorbidities should avoid cyclosporine as a treatment option.

Acitretin, an FDA-approved oral retinoid, is an optimal treatment option for immunosuppressed patients or patients with HIV on antiretroviral therapy because it is not immunosuppressive.⁴ Unlike cyclosporine, acitretin is less helpful for acute flares because it takes 3 to 6 months to reach peak therapeutic response for treating plaque psoriasis. Similar to cyclosporine, acitretin can be recommended for severe psoriatic variants of erythrodermic, generalized pustular, and palmoplantar psoriasis. Acitretin has been reported to be more effective and have a more rapid onset of action in erythrodermic and pustular psoriasis than in plaque psoriasis.⁵

Patient Comorbidities

Psoriatic arthritis (PsA) is a common comorbidity that affects treatment choice. Patients with coexisting PsA could be treated with apremilast, as it is approved for both psoriasis and PsA. In a phase 3 randomized, controlled trial, American College of Rheumatology (ACR) 20 response at weeks 16 and 52 was achieved by significantly more patients on apremilast at 20 mg twice daily (BID)(P=.0166) or 30 mg BID (P=.0001) than placebo.⁶ Although not FDA approved for PsA, methotrexate has been shown to improve concomitant PsA of the peripheral joints in patients with psoriasis. Furthermore, a trial of methotrexate has shown considerable improvements in PsA symptoms in patients with psoriasis—a 62.7% decrease in proportion of patients with dactylitis, 25.7% decrease in enthesitis, and improvements in ACR outcomes (ACR20 in 40.8%, ACR50 in 18.8%, and ACR70 in 8.6%, with 22.4% achieving minimal disease activity).⁷

Prior to starting a systemic medication for psoriasis, it is necessary to discuss effects on pregnancy and fertility. Pregnancy is an absolute contraindication for methotrexate and acitretin use because of the drugs’ teratogenicity. Fetal death and fetal abnormalities have been reported with methotrexate use in pregnant women.⁸ Bone, central nervous system, auditory, ocular, and cardiovascular fetal abnormalities have been reported with maternal acitretin use.⁹ Breastfeeding also is an absolute contraindication for methotrexate use, as methotrexate passes into breastmilk in small quantities. Patients taking acitretin also are strongly discouraged from nursing because of the long half-life (168 days) of etretinate, a reverse metabolism product of acitretin that is increased in the presence of alcohol. Women should wait 3 months after discontinuing methotrexate for complete drug clearance before conceiving compared to 3 years in women who have discontinued acitretin.^8,10 Men also are recommended to wait 3 months after discontinuing methotrexate before attempting to conceive, as its effect on male spermatogenesis and teratogenicity is unclear. Acitretin has no documented teratogenic effect in men. For women planning to become pregnant, apremilast and cyclosporine can be continued throughout pregnancy on an individual basis. The benefit of apremilast should be weighed against its potential risk to the fetus. There is no evidence of teratogenicity of apremilast at doses of 20 mg/kg daily.¹¹ Current research regarding cyclosporine use in pregnancy only exists in transplant patients and has revealed higher rates of prematurity and lower birth weight without teratogenic effects.^10,12 The risks and benefits of continuing cyclosporine while nursing should be evaluated, as cyclosporine (and ethanol-methanol components used in some formulations) is detectable in breast milk.

Drug Contraindications

Hypersensitivity to a specific systemic nonbiologic medication is a contraindication to its use and is an absolute contraindication for methotrexate. Other absolute contraindications to methotrexate are pregnancy and nursing, alcoholism, alcoholic liver disease, chronic liver disease, immunodeficiency, and cytopenia. Contraindications to acitretin include pregnancy, severely impaired liver and kidney function, and chronic abnormally elevated lipid levels. There are no additional contraindications for apremilast, but patients must be informed of the risk for depression before initiating therapy. Cyclosporine is contraindicated in patients with prior psoralen plus UVA (PUVA) treatment or radiation therapy, abnormal renal function, uncontrolled hypertension, uncontrolled and active infections, and a history of systemic malignancy. Live vaccines should be avoided in patients on cyclosporine, and caution is advised when cyclosporine is prescribed for patients with poorly controlled diabetes.

Pretreatment Screening

Because of drug interactions, a detailed medication history is essential prior to starting any systemic medication for psoriasis. Apremilast and cyclosporine are metabolized by cytochrome P450 and therefore are more susceptible to drug-related interactions. Cyclosporine use can affect levels of other medications that are metabolized by cytochrome P450, such as statins, calcium channel blockers, and warfarin. Similarly, acitretin’s metabolism is affected by drugs that interfere with cytochrome P450. Additionally, screening laboratory tests are needed before initiating systemic nonbiologic agents for psoriasis, with the exception of apremilast.

Prior to initiating methotrexate treatment, patients may require tuberculosis (TB), hepatitis B, and hepatitis C screening tests, depending on their risk factors. A baseline liver fibrosis assessment is recommended because of the potential of hepatotoxicity in patients receiving methotrexate. Noninvasive serology tests utilized to evaluate the presence of pre-existing liver disease include Fibrosis-4, FibroMeter, FibroSure, and Hepascore. Patients with impaired renal function have an increased predisposition to methotrexate-induced hematologic toxicity. Thus, it is necessary to administer a test dose of methotrexate in these patients followed by a complete blood cell count (CBC) 5 to 7 days later. An unremarkable CBC after the test dose suggests the absence of myelosuppression, and methotrexate dosage can be increased weekly. Patients on methotrexate also must receive folate supplementation to reduce the risk for adverse effects during treatment.

Patients considering cyclosporine must undergo screening for family and personal history of renal disease. Prior to initiating treatment, patients require 2 blood pressure measurements, hepatitis screening, TB screening, urinalysis, serum creatinine (Cr), blood urea nitrogen (BUN), CBC, potassium and magnesium levels, uric acid levels, lipid profile, bilirubin, and liver function tests (LFTs). A pregnancy test also is warranted for women of childbearing potential (WOCP).

Patients receiving acitretin should receive screening laboratory tests consisting of fasting cholesterol and triglycerides, CBC, renal function tests, LFTs, and a pregnancy test, if applicable.

After baseline evaluations, the selected oral systemic can be initiated using specific dosing regimens to ensure optimal drug efficacy and reduce incidence of adverse effects (eTable).

Monitoring During Active Treatment

Physicians need to counsel patients on potential adverse effects of their medications. Because of its relatively safe profile among the systemic nonbiologic agents, apremilast requires the least monitoring during treatment. There is no required routine laboratory monitoring for patients using apremilast, though testing may be pursued at the clinician’s discretion. However, weight should be regularly measured in patients on apremilast. In a phase 3 clinical trial of patients with psoriasis, 12% of patients on apremilast experienced a 5% to 10% weight loss compared to 5% of patients on placebo.^11,13 Thus, it is recommended that physicians consider discontinuing apremilast in patients with a weight loss of more than 5% from baseline, especially if it may lead to other unfavorable health effects. Because depression is reported among 1% of patients on apremilast, close monitoring for new or worsening symptoms of depression should be performed during treatment.^11,13 To avoid common GI side effects, apremilast is initiated at 10 mg/d and is increased by 10 mg/d over the first 5 days to a final dose of 30 mg BID. Elderly patients in particular should be cautioned about the risk of dehydration associated with GI side effects. Patients with severe renal impairment (Cr clearance, <30 mL/min) should use apremilast at a dosage of 30 mg once daily.

For patients on methotrexate, laboratory monitoring is essential after each dose increase. It also is important for physicians to obtain regular blood work to assess for hematologic abnormalities and hepatoxicity. Patients with risk factors such as renal insufficiency, increased age, hypoalbuminemia, alcohol abuse and alcoholic liver disease, and methotrexate dosing errors, as well as those prone to drug-related interactions, must be monitored closely for pancytopenia.^14,15 The protocol for screening for methotrexate-induced hepatotoxicity during treatment depends on patient risk factors. Risk factors for hepatoxicity include history of or current alcohol abuse, abnormal LFTs, personal or family history of liver disease, diabetes, obesity, use of other hepatotoxic drugs, and hyperlipidemia.¹⁶ In patients without blood work abnormalities, CBC and LFTs can be performed every 3 to 6 months. Patients with abnormally elevated LFTs require repeat blood work every 2 to 4 weeks. Persistent elevations in LFTs require further evaluation by a GI specialist. After a cumulative dose of 3.5 to 4 g, patients should receive a GI referral and further studies (such as vibration-controlled transient elastography or liver biopsy) to assess for liver fibrosis. Patients with signs of stage 3 liver fibrosis are recommended to discontinue methotrexate and switch to another medication for psoriasis. For patients with impaired renal function, periodic BUN and Cr monitoring are needed. Common adverse effects of methotrexate include diarrhea, nausea, and anorexia, which can be mitigated by taking methotrexate with food or lowering the dosage.⁸ Patients on methotrexate should be monitored for rare but potential risks of infection and reactivation of latent TB, hepatitis, and lymphoma. To reduce the incidence of methotrexate toxicity from drug interactions, a review of current medications at each follow-up visit is recommended.

Nephrotoxicity and hypertension are the most common adverse effects of cyclosporine. It is important to monitor BUN and Cr biweekly for the initial 3 months, then at monthly intervals if there are no persistent abnormalities. Patients also must receive monthly CBC, potassium and magnesium levels, uric acid levels, lipid panel, serum bilirubin, and LFTs to monitor for adverse effects.¹⁷ Physicians should obtain regular pregnancy tests in WOCP. Weekly monitoring of early-morning blood pressure is recommended for patients on cyclosporine to detect early cyclosporine-induced nephrotoxicity. Hypertension on 2 separate occasions warrants a reduction in cyclosporine dosage or an addition of a calcium channel blocker for blood pressure control. Dose reduction also should be performed in patients with an increase in Cr above baseline greater than 25%.¹⁷ If Cr level is persistently elevated or if blood pressure does not normalize to lower than 140/90 after dose reduction, cyclosporine should be immediately discontinued. Patients on cyclosporine for more than a year warrant an annual estimation of glomerular filtration rate because of irreversible kidney damage associated with long-term use. A systematic review of patients treated with cyclosporine for more than 2 years found that at least 50% of patients experienced a 30% increase in Cr above baseline.¹⁸

Patients taking acitretin should be monitored for hyperlipidemia, the most common laboratory abnormality seen in 25% to 50% of patients.¹⁹ Fasting lipid panel and LFTs should be performed monthly for the initial 3 months on acitretin, then at 3-month intervals. Lifestyle changes should be encouraged to reduce hyperlipidemia, and fibrates may be given to treat elevated triglyceride levels, the most common type of hyperlipidemia seen with acitretin. Acitretin-induced toxic hepatitis is a rare occurrence that warrants immediate discontinuation of the medication.²⁰ Monthly pregnancy tests must be performed in WOCP.

Combination Therapy

For apremilast, there is anecdotal evidence supporting its use in conjunction with phototherapy or biologics in some cases, but no high-quality data.²¹ On the other hand, using combination therapy with other systemic therapies can reduce adverse effects and decrease the amount of medication needed to achieve psoriasis clearance. Methotrexate used with etanercept, for example, has been more effective than methotrexate monotherapy in treating psoriasis, which has been attributed to a methotrexate-mediated reduction in the production of antidrug antibodies.^22,23

Methotrexate, cyclosporine, and acitretin have synergistic effects when used with phototherapy. Narrowband UVB (NB-UVB) phototherapy combined with methotrexate is more effective in clearing psoriasis than methotrexate or NB-UVB phototherapy alone. Similarly, acitretin and PUVA combination therapy is more effective than acitretin or PUVA phototherapy alone. Combination regimens of acitretin and broadband UVB phototherapy, acitretin and NB-UVB phototherapy, and acitretin and PUVA phototherapy also have been more effective than individual modalities alone. Combination therapy reduces the cumulative doses of both therapies and reduces the frequency and duration of phototherapy needed for psoriatic clearance.²⁴ In acitretin combination therapy with UVB phototherapy, the recommended regimen is 2 weeks of acitretin monotherapy followed by UVB phototherapy. For patients with an inadequate response to UVB phototherapy, the UVB dose can be reduced by 30% to 50%, and acitretin 25 mg/d can be added to phototherapy treatment. Acitretin-UVB combination therapy has been shown to reduce the risk of UVB-induced erythema seen in UVB monotherapy. Similarly, the risk of squamous cell carcinoma is reduced in acitretin-PUVA combination therapy compared to PUVA monotherapy.²⁵

The timing of phototherapy in combination with systemic nonbiologic agents is critical. Phototherapy used simultaneously with cyclosporine is contraindicated owing to increased risk of photocarcinogenesis, whereas phototherapy used in sequence with cyclosporine is well tolerated and effective. Furthermore, cyclosporine 3 mg/kg/d for 4 weeks followed by a rapid cyclosporine taper and initiation of NB-UVB phototherapy demonstrated resolution of psoriasis with fewer NB-UVB treatments and less UVB exposure than NB-UVB therapy alone.²⁶

Final Thoughts

The FDA-approved systemic nonbiologic agents are accessible and effective treatment options for adults with widespread or inadequately controlled psoriasis. Selecting the ideal therapy requires careful consideration of medication toxicity, contraindications, monitoring requirements, and patient comorbidities. The AAD-NPF guidelines guide dermatologists in prescribing systemic nonbiologic treatments in adults with psoriasis. Utilizing these recommendations in combination with clinician judgment will help patients achieve safe and optimal psoriasis clearance.

Psoriasis is a chronic relapsing skin condition characterized by keratinocyte hyperproliferation and a chronic inflammatory cascade. Therefore, controlling inflammatory responses with systemic medications is beneficial in managing psoriatic lesions and their accompanying symptoms, especially in disease inadequately controlled by topicals. Ease of drug administration and treatment availability are benefits that systemic nonbiologic therapies may have over biologic therapies.

In 2020, the American Academy of Dermatology (AAD) and the National Psoriasis Foundation (NPF) published guidelines for managing psoriasis in adults with systemic nonbiologic therapies.¹ Dosing, efficacy, toxicity, drug-related interactions, and contraindications are addressed alongside evidence-based treatment recommendations. This review addresses current recommendations for systemic nonbiologics in psoriasis with a focus on the treatments approved by the US Food and Drug Administration (FDA): acitretin, apremilast, cyclosporine, and methotrexate (eTable). Fumaric acid esters and tofacitinib are FDA approved for psoriatic arthritis but not for plaque psoriasis. Additional long-term safety analyses of tofacitinib for plaque psoriasis were requested by the FDA. Dimethyl fumarate is approved by the European Medicines Agency for treatment of psoriasis and is among the first-line systemic treatments used in Germany.²

Selecting a Systemic Nonbiologic Agent

Methotrexate and apremilast have a strength level A recommendation for treating moderate to severe psoriasis in adults. However, methotrexate is less effective than biologic agents, including adalimumab and infliximab, for cutaneous psoriasis. Methotrexate is believed to improve psoriasis because of its direct immunosuppressive effect and inhibition of lymphoid cell proliferation. It typically is administered orally but can be administered subcutaneously for decreased gastrointestinal (GI) adverse effects. Compliance with close laboratory monitoring and lifestyle modifications, such as contraceptive use (because of teratogenicity) and alcohol cessation (because of the risk of liver damage) are essential in patients using methotrexate.

Apremilast, the most recently FDA-approved oral systemic medication for psoriasis, inhibits phosphodiesterase 4, subsequently decreasing inflammatory responses involving helper T cells T_H1 and T_H17 as well as type 1 interferon pathways. Apremilast is particularly effective in treating psoriasis with scalp and palmoplantar involvement.³ Additionally, it has an encouraging safety profile and is favorable in patients with multiple comorbidities.

Among the 4 oral agents, cyclosporine has the quickest onset of effect and has a strength level A recommendation for treating severe and recalcitrant psoriasis. Because of its high-risk profile, it is recommended for short periods of time, acute flares, or during transitions to safer long-term treatment. Patients with multiple comorbidities should avoid cyclosporine as a treatment option.

Acitretin, an FDA-approved oral retinoid, is an optimal treatment option for immunosuppressed patients or patients with HIV on antiretroviral therapy because it is not immunosuppressive.⁴ Unlike cyclosporine, acitretin is less helpful for acute flares because it takes 3 to 6 months to reach peak therapeutic response for treating plaque psoriasis. Similar to cyclosporine, acitretin can be recommended for severe psoriatic variants of erythrodermic, generalized pustular, and palmoplantar psoriasis. Acitretin has been reported to be more effective and have a more rapid onset of action in erythrodermic and pustular psoriasis than in plaque psoriasis.⁵

Patient Comorbidities

Psoriatic arthritis (PsA) is a common comorbidity that affects treatment choice. Patients with coexisting PsA could be treated with apremilast, as it is approved for both psoriasis and PsA. In a phase 3 randomized, controlled trial, American College of Rheumatology (ACR) 20 response at weeks 16 and 52 was achieved by significantly more patients on apremilast at 20 mg twice daily (BID)(P=.0166) or 30 mg BID (P=.0001) than placebo.⁶ Although not FDA approved for PsA, methotrexate has been shown to improve concomitant PsA of the peripheral joints in patients with psoriasis. Furthermore, a trial of methotrexate has shown considerable improvements in PsA symptoms in patients with psoriasis—a 62.7% decrease in proportion of patients with dactylitis, 25.7% decrease in enthesitis, and improvements in ACR outcomes (ACR20 in 40.8%, ACR50 in 18.8%, and ACR70 in 8.6%, with 22.4% achieving minimal disease activity).⁷

Prior to starting a systemic medication for psoriasis, it is necessary to discuss effects on pregnancy and fertility. Pregnancy is an absolute contraindication for methotrexate and acitretin use because of the drugs’ teratogenicity. Fetal death and fetal abnormalities have been reported with methotrexate use in pregnant women.⁸ Bone, central nervous system, auditory, ocular, and cardiovascular fetal abnormalities have been reported with maternal acitretin use.⁹ Breastfeeding also is an absolute contraindication for methotrexate use, as methotrexate passes into breastmilk in small quantities. Patients taking acitretin also are strongly discouraged from nursing because of the long half-life (168 days) of etretinate, a reverse metabolism product of acitretin that is increased in the presence of alcohol. Women should wait 3 months after discontinuing methotrexate for complete drug clearance before conceiving compared to 3 years in women who have discontinued acitretin.^8,10 Men also are recommended to wait 3 months after discontinuing methotrexate before attempting to conceive, as its effect on male spermatogenesis and teratogenicity is unclear. Acitretin has no documented teratogenic effect in men. For women planning to become pregnant, apremilast and cyclosporine can be continued throughout pregnancy on an individual basis. The benefit of apremilast should be weighed against its potential risk to the fetus. There is no evidence of teratogenicity of apremilast at doses of 20 mg/kg daily.¹¹ Current research regarding cyclosporine use in pregnancy only exists in transplant patients and has revealed higher rates of prematurity and lower birth weight without teratogenic effects.^10,12 The risks and benefits of continuing cyclosporine while nursing should be evaluated, as cyclosporine (and ethanol-methanol components used in some formulations) is detectable in breast milk.

Drug Contraindications

Hypersensitivity to a specific systemic nonbiologic medication is a contraindication to its use and is an absolute contraindication for methotrexate. Other absolute contraindications to methotrexate are pregnancy and nursing, alcoholism, alcoholic liver disease, chronic liver disease, immunodeficiency, and cytopenia. Contraindications to acitretin include pregnancy, severely impaired liver and kidney function, and chronic abnormally elevated lipid levels. There are no additional contraindications for apremilast, but patients must be informed of the risk for depression before initiating therapy. Cyclosporine is contraindicated in patients with prior psoralen plus UVA (PUVA) treatment or radiation therapy, abnormal renal function, uncontrolled hypertension, uncontrolled and active infections, and a history of systemic malignancy. Live vaccines should be avoided in patients on cyclosporine, and caution is advised when cyclosporine is prescribed for patients with poorly controlled diabetes.

Pretreatment Screening

Because of drug interactions, a detailed medication history is essential prior to starting any systemic medication for psoriasis. Apremilast and cyclosporine are metabolized by cytochrome P450 and therefore are more susceptible to drug-related interactions. Cyclosporine use can affect levels of other medications that are metabolized by cytochrome P450, such as statins, calcium channel blockers, and warfarin. Similarly, acitretin’s metabolism is affected by drugs that interfere with cytochrome P450. Additionally, screening laboratory tests are needed before initiating systemic nonbiologic agents for psoriasis, with the exception of apremilast.

Prior to initiating methotrexate treatment, patients may require tuberculosis (TB), hepatitis B, and hepatitis C screening tests, depending on their risk factors. A baseline liver fibrosis assessment is recommended because of the potential of hepatotoxicity in patients receiving methotrexate. Noninvasive serology tests utilized to evaluate the presence of pre-existing liver disease include Fibrosis-4, FibroMeter, FibroSure, and Hepascore. Patients with impaired renal function have an increased predisposition to methotrexate-induced hematologic toxicity. Thus, it is necessary to administer a test dose of methotrexate in these patients followed by a complete blood cell count (CBC) 5 to 7 days later. An unremarkable CBC after the test dose suggests the absence of myelosuppression, and methotrexate dosage can be increased weekly. Patients on methotrexate also must receive folate supplementation to reduce the risk for adverse effects during treatment.

Patients considering cyclosporine must undergo screening for family and personal history of renal disease. Prior to initiating treatment, patients require 2 blood pressure measurements, hepatitis screening, TB screening, urinalysis, serum creatinine (Cr), blood urea nitrogen (BUN), CBC, potassium and magnesium levels, uric acid levels, lipid profile, bilirubin, and liver function tests (LFTs). A pregnancy test also is warranted for women of childbearing potential (WOCP).

Patients receiving acitretin should receive screening laboratory tests consisting of fasting cholesterol and triglycerides, CBC, renal function tests, LFTs, and a pregnancy test, if applicable.

After baseline evaluations, the selected oral systemic can be initiated using specific dosing regimens to ensure optimal drug efficacy and reduce incidence of adverse effects (eTable).

Monitoring During Active Treatment

Physicians need to counsel patients on potential adverse effects of their medications. Because of its relatively safe profile among the systemic nonbiologic agents, apremilast requires the least monitoring during treatment. There is no required routine laboratory monitoring for patients using apremilast, though testing may be pursued at the clinician’s discretion. However, weight should be regularly measured in patients on apremilast. In a phase 3 clinical trial of patients with psoriasis, 12% of patients on apremilast experienced a 5% to 10% weight loss compared to 5% of patients on placebo.^11,13 Thus, it is recommended that physicians consider discontinuing apremilast in patients with a weight loss of more than 5% from baseline, especially if it may lead to other unfavorable health effects. Because depression is reported among 1% of patients on apremilast, close monitoring for new or worsening symptoms of depression should be performed during treatment.^11,13 To avoid common GI side effects, apremilast is initiated at 10 mg/d and is increased by 10 mg/d over the first 5 days to a final dose of 30 mg BID. Elderly patients in particular should be cautioned about the risk of dehydration associated with GI side effects. Patients with severe renal impairment (Cr clearance, <30 mL/min) should use apremilast at a dosage of 30 mg once daily.

For patients on methotrexate, laboratory monitoring is essential after each dose increase. It also is important for physicians to obtain regular blood work to assess for hematologic abnormalities and hepatoxicity. Patients with risk factors such as renal insufficiency, increased age, hypoalbuminemia, alcohol abuse and alcoholic liver disease, and methotrexate dosing errors, as well as those prone to drug-related interactions, must be monitored closely for pancytopenia.^14,15 The protocol for screening for methotrexate-induced hepatotoxicity during treatment depends on patient risk factors. Risk factors for hepatoxicity include history of or current alcohol abuse, abnormal LFTs, personal or family history of liver disease, diabetes, obesity, use of other hepatotoxic drugs, and hyperlipidemia.¹⁶ In patients without blood work abnormalities, CBC and LFTs can be performed every 3 to 6 months. Patients with abnormally elevated LFTs require repeat blood work every 2 to 4 weeks. Persistent elevations in LFTs require further evaluation by a GI specialist. After a cumulative dose of 3.5 to 4 g, patients should receive a GI referral and further studies (such as vibration-controlled transient elastography or liver biopsy) to assess for liver fibrosis. Patients with signs of stage 3 liver fibrosis are recommended to discontinue methotrexate and switch to another medication for psoriasis. For patients with impaired renal function, periodic BUN and Cr monitoring are needed. Common adverse effects of methotrexate include diarrhea, nausea, and anorexia, which can be mitigated by taking methotrexate with food or lowering the dosage.⁸ Patients on methotrexate should be monitored for rare but potential risks of infection and reactivation of latent TB, hepatitis, and lymphoma. To reduce the incidence of methotrexate toxicity from drug interactions, a review of current medications at each follow-up visit is recommended.

Nephrotoxicity and hypertension are the most common adverse effects of cyclosporine. It is important to monitor BUN and Cr biweekly for the initial 3 months, then at monthly intervals if there are no persistent abnormalities. Patients also must receive monthly CBC, potassium and magnesium levels, uric acid levels, lipid panel, serum bilirubin, and LFTs to monitor for adverse effects.¹⁷ Physicians should obtain regular pregnancy tests in WOCP. Weekly monitoring of early-morning blood pressure is recommended for patients on cyclosporine to detect early cyclosporine-induced nephrotoxicity. Hypertension on 2 separate occasions warrants a reduction in cyclosporine dosage or an addition of a calcium channel blocker for blood pressure control. Dose reduction also should be performed in patients with an increase in Cr above baseline greater than 25%.¹⁷ If Cr level is persistently elevated or if blood pressure does not normalize to lower than 140/90 after dose reduction, cyclosporine should be immediately discontinued. Patients on cyclosporine for more than a year warrant an annual estimation of glomerular filtration rate because of irreversible kidney damage associated with long-term use. A systematic review of patients treated with cyclosporine for more than 2 years found that at least 50% of patients experienced a 30% increase in Cr above baseline.¹⁸

Patients taking acitretin should be monitored for hyperlipidemia, the most common laboratory abnormality seen in 25% to 50% of patients.¹⁹ Fasting lipid panel and LFTs should be performed monthly for the initial 3 months on acitretin, then at 3-month intervals. Lifestyle changes should be encouraged to reduce hyperlipidemia, and fibrates may be given to treat elevated triglyceride levels, the most common type of hyperlipidemia seen with acitretin. Acitretin-induced toxic hepatitis is a rare occurrence that warrants immediate discontinuation of the medication.²⁰ Monthly pregnancy tests must be performed in WOCP.

Combination Therapy

For apremilast, there is anecdotal evidence supporting its use in conjunction with phototherapy or biologics in some cases, but no high-quality data.²¹ On the other hand, using combination therapy with other systemic therapies can reduce adverse effects and decrease the amount of medication needed to achieve psoriasis clearance. Methotrexate used with etanercept, for example, has been more effective than methotrexate monotherapy in treating psoriasis, which has been attributed to a methotrexate-mediated reduction in the production of antidrug antibodies.^22,23

Methotrexate, cyclosporine, and acitretin have synergistic effects when used with phototherapy. Narrowband UVB (NB-UVB) phototherapy combined with methotrexate is more effective in clearing psoriasis than methotrexate or NB-UVB phototherapy alone. Similarly, acitretin and PUVA combination therapy is more effective than acitretin or PUVA phototherapy alone. Combination regimens of acitretin and broadband UVB phototherapy, acitretin and NB-UVB phototherapy, and acitretin and PUVA phototherapy also have been more effective than individual modalities alone. Combination therapy reduces the cumulative doses of both therapies and reduces the frequency and duration of phototherapy needed for psoriatic clearance.²⁴ In acitretin combination therapy with UVB phototherapy, the recommended regimen is 2 weeks of acitretin monotherapy followed by UVB phototherapy. For patients with an inadequate response to UVB phototherapy, the UVB dose can be reduced by 30% to 50%, and acitretin 25 mg/d can be added to phototherapy treatment. Acitretin-UVB combination therapy has been shown to reduce the risk of UVB-induced erythema seen in UVB monotherapy. Similarly, the risk of squamous cell carcinoma is reduced in acitretin-PUVA combination therapy compared to PUVA monotherapy.²⁵

The timing of phototherapy in combination with systemic nonbiologic agents is critical. Phototherapy used simultaneously with cyclosporine is contraindicated owing to increased risk of photocarcinogenesis, whereas phototherapy used in sequence with cyclosporine is well tolerated and effective. Furthermore, cyclosporine 3 mg/kg/d for 4 weeks followed by a rapid cyclosporine taper and initiation of NB-UVB phototherapy demonstrated resolution of psoriasis with fewer NB-UVB treatments and less UVB exposure than NB-UVB therapy alone.²⁶

Final Thoughts

The FDA-approved systemic nonbiologic agents are accessible and effective treatment options for adults with widespread or inadequately controlled psoriasis. Selecting the ideal therapy requires careful consideration of medication toxicity, contraindications, monitoring requirements, and patient comorbidities. The AAD-NPF guidelines guide dermatologists in prescribing systemic nonbiologic treatments in adults with psoriasis. Utilizing these recommendations in combination with clinician judgment will help patients achieve safe and optimal psoriasis clearance.

Psoriasis is a chronic relapsing skin condition characterized by keratinocyte hyperproliferation and a chronic inflammatory cascade. Therefore, controlling inflammatory responses with systemic medications is beneficial in managing psoriatic lesions and their accompanying symptoms, especially in disease inadequately controlled by topicals. Ease of drug administration and treatment availability are benefits that systemic nonbiologic therapies may have over biologic therapies.

In 2020, the American Academy of Dermatology (AAD) and the National Psoriasis Foundation (NPF) published guidelines for managing psoriasis in adults with systemic nonbiologic therapies.¹ Dosing, efficacy, toxicity, drug-related interactions, and contraindications are addressed alongside evidence-based treatment recommendations. This review addresses current recommendations for systemic nonbiologics in psoriasis with a focus on the treatments approved by the US Food and Drug Administration (FDA): acitretin, apremilast, cyclosporine, and methotrexate (eTable). Fumaric acid esters and tofacitinib are FDA approved for psoriatic arthritis but not for plaque psoriasis. Additional long-term safety analyses of tofacitinib for plaque psoriasis were requested by the FDA. Dimethyl fumarate is approved by the European Medicines Agency for treatment of psoriasis and is among the first-line systemic treatments used in Germany.²

Selecting a Systemic Nonbiologic Agent

Methotrexate and apremilast have a strength level A recommendation for treating moderate to severe psoriasis in adults. However, methotrexate is less effective than biologic agents, including adalimumab and infliximab, for cutaneous psoriasis. Methotrexate is believed to improve psoriasis because of its direct immunosuppressive effect and inhibition of lymphoid cell proliferation. It typically is administered orally but can be administered subcutaneously for decreased gastrointestinal (GI) adverse effects. Compliance with close laboratory monitoring and lifestyle modifications, such as contraceptive use (because of teratogenicity) and alcohol cessation (because of the risk of liver damage) are essential in patients using methotrexate.

Apremilast, the most recently FDA-approved oral systemic medication for psoriasis, inhibits phosphodiesterase 4, subsequently decreasing inflammatory responses involving helper T cells T_H1 and T_H17 as well as type 1 interferon pathways. Apremilast is particularly effective in treating psoriasis with scalp and palmoplantar involvement.³ Additionally, it has an encouraging safety profile and is favorable in patients with multiple comorbidities.

Among the 4 oral agents, cyclosporine has the quickest onset of effect and has a strength level A recommendation for treating severe and recalcitrant psoriasis. Because of its high-risk profile, it is recommended for short periods of time, acute flares, or during transitions to safer long-term treatment. Patients with multiple comorbidities should avoid cyclosporine as a treatment option.

Acitretin, an FDA-approved oral retinoid, is an optimal treatment option for immunosuppressed patients or patients with HIV on antiretroviral therapy because it is not immunosuppressive.⁴ Unlike cyclosporine, acitretin is less helpful for acute flares because it takes 3 to 6 months to reach peak therapeutic response for treating plaque psoriasis. Similar to cyclosporine, acitretin can be recommended for severe psoriatic variants of erythrodermic, generalized pustular, and palmoplantar psoriasis. Acitretin has been reported to be more effective and have a more rapid onset of action in erythrodermic and pustular psoriasis than in plaque psoriasis.⁵

Patient Comorbidities

Psoriatic arthritis (PsA) is a common comorbidity that affects treatment choice. Patients with coexisting PsA could be treated with apremilast, as it is approved for both psoriasis and PsA. In a phase 3 randomized, controlled trial, American College of Rheumatology (ACR) 20 response at weeks 16 and 52 was achieved by significantly more patients on apremilast at 20 mg twice daily (BID)(P=.0166) or 30 mg BID (P=.0001) than placebo.⁶ Although not FDA approved for PsA, methotrexate has been shown to improve concomitant PsA of the peripheral joints in patients with psoriasis. Furthermore, a trial of methotrexate has shown considerable improvements in PsA symptoms in patients with psoriasis—a 62.7% decrease in proportion of patients with dactylitis, 25.7% decrease in enthesitis, and improvements in ACR outcomes (ACR20 in 40.8%, ACR50 in 18.8%, and ACR70 in 8.6%, with 22.4% achieving minimal disease activity).⁷

Prior to starting a systemic medication for psoriasis, it is necessary to discuss effects on pregnancy and fertility. Pregnancy is an absolute contraindication for methotrexate and acitretin use because of the drugs’ teratogenicity. Fetal death and fetal abnormalities have been reported with methotrexate use in pregnant women.⁸ Bone, central nervous system, auditory, ocular, and cardiovascular fetal abnormalities have been reported with maternal acitretin use.⁹ Breastfeeding also is an absolute contraindication for methotrexate use, as methotrexate passes into breastmilk in small quantities. Patients taking acitretin also are strongly discouraged from nursing because of the long half-life (168 days) of etretinate, a reverse metabolism product of acitretin that is increased in the presence of alcohol. Women should wait 3 months after discontinuing methotrexate for complete drug clearance before conceiving compared to 3 years in women who have discontinued acitretin.^8,10 Men also are recommended to wait 3 months after discontinuing methotrexate before attempting to conceive, as its effect on male spermatogenesis and teratogenicity is unclear. Acitretin has no documented teratogenic effect in men. For women planning to become pregnant, apremilast and cyclosporine can be continued throughout pregnancy on an individual basis. The benefit of apremilast should be weighed against its potential risk to the fetus. There is no evidence of teratogenicity of apremilast at doses of 20 mg/kg daily.¹¹ Current research regarding cyclosporine use in pregnancy only exists in transplant patients and has revealed higher rates of prematurity and lower birth weight without teratogenic effects.^10,12 The risks and benefits of continuing cyclosporine while nursing should be evaluated, as cyclosporine (and ethanol-methanol components used in some formulations) is detectable in breast milk.

Drug Contraindications

Hypersensitivity to a specific systemic nonbiologic medication is a contraindication to its use and is an absolute contraindication for methotrexate. Other absolute contraindications to methotrexate are pregnancy and nursing, alcoholism, alcoholic liver disease, chronic liver disease, immunodeficiency, and cytopenia. Contraindications to acitretin include pregnancy, severely impaired liver and kidney function, and chronic abnormally elevated lipid levels. There are no additional contraindications for apremilast, but patients must be informed of the risk for depression before initiating therapy. Cyclosporine is contraindicated in patients with prior psoralen plus UVA (PUVA) treatment or radiation therapy, abnormal renal function, uncontrolled hypertension, uncontrolled and active infections, and a history of systemic malignancy. Live vaccines should be avoided in patients on cyclosporine, and caution is advised when cyclosporine is prescribed for patients with poorly controlled diabetes.

Pretreatment Screening

Because of drug interactions, a detailed medication history is essential prior to starting any systemic medication for psoriasis. Apremilast and cyclosporine are metabolized by cytochrome P450 and therefore are more susceptible to drug-related interactions. Cyclosporine use can affect levels of other medications that are metabolized by cytochrome P450, such as statins, calcium channel blockers, and warfarin. Similarly, acitretin’s metabolism is affected by drugs that interfere with cytochrome P450. Additionally, screening laboratory tests are needed before initiating systemic nonbiologic agents for psoriasis, with the exception of apremilast.

Prior to initiating methotrexate treatment, patients may require tuberculosis (TB), hepatitis B, and hepatitis C screening tests, depending on their risk factors. A baseline liver fibrosis assessment is recommended because of the potential of hepatotoxicity in patients receiving methotrexate. Noninvasive serology tests utilized to evaluate the presence of pre-existing liver disease include Fibrosis-4, FibroMeter, FibroSure, and Hepascore. Patients with impaired renal function have an increased predisposition to methotrexate-induced hematologic toxicity. Thus, it is necessary to administer a test dose of methotrexate in these patients followed by a complete blood cell count (CBC) 5 to 7 days later. An unremarkable CBC after the test dose suggests the absence of myelosuppression, and methotrexate dosage can be increased weekly. Patients on methotrexate also must receive folate supplementation to reduce the risk for adverse effects during treatment.

Patients considering cyclosporine must undergo screening for family and personal history of renal disease. Prior to initiating treatment, patients require 2 blood pressure measurements, hepatitis screening, TB screening, urinalysis, serum creatinine (Cr), blood urea nitrogen (BUN), CBC, potassium and magnesium levels, uric acid levels, lipid profile, bilirubin, and liver function tests (LFTs). A pregnancy test also is warranted for women of childbearing potential (WOCP).

Patients receiving acitretin should receive screening laboratory tests consisting of fasting cholesterol and triglycerides, CBC, renal function tests, LFTs, and a pregnancy test, if applicable.

After baseline evaluations, the selected oral systemic can be initiated using specific dosing regimens to ensure optimal drug efficacy and reduce incidence of adverse effects (eTable).

Monitoring During Active Treatment

Physicians need to counsel patients on potential adverse effects of their medications. Because of its relatively safe profile among the systemic nonbiologic agents, apremilast requires the least monitoring during treatment. There is no required routine laboratory monitoring for patients using apremilast, though testing may be pursued at the clinician’s discretion. However, weight should be regularly measured in patients on apremilast. In a phase 3 clinical trial of patients with psoriasis, 12% of patients on apremilast experienced a 5% to 10% weight loss compared to 5% of patients on placebo.^11,13 Thus, it is recommended that physicians consider discontinuing apremilast in patients with a weight loss of more than 5% from baseline, especially if it may lead to other unfavorable health effects. Because depression is reported among 1% of patients on apremilast, close monitoring for new or worsening symptoms of depression should be performed during treatment.^11,13 To avoid common GI side effects, apremilast is initiated at 10 mg/d and is increased by 10 mg/d over the first 5 days to a final dose of 30 mg BID. Elderly patients in particular should be cautioned about the risk of dehydration associated with GI side effects. Patients with severe renal impairment (Cr clearance, <30 mL/min) should use apremilast at a dosage of 30 mg once daily.

For patients on methotrexate, laboratory monitoring is essential after each dose increase. It also is important for physicians to obtain regular blood work to assess for hematologic abnormalities and hepatoxicity. Patients with risk factors such as renal insufficiency, increased age, hypoalbuminemia, alcohol abuse and alcoholic liver disease, and methotrexate dosing errors, as well as those prone to drug-related interactions, must be monitored closely for pancytopenia.^14,15 The protocol for screening for methotrexate-induced hepatotoxicity during treatment depends on patient risk factors. Risk factors for hepatoxicity include history of or current alcohol abuse, abnormal LFTs, personal or family history of liver disease, diabetes, obesity, use of other hepatotoxic drugs, and hyperlipidemia.¹⁶ In patients without blood work abnormalities, CBC and LFTs can be performed every 3 to 6 months. Patients with abnormally elevated LFTs require repeat blood work every 2 to 4 weeks. Persistent elevations in LFTs require further evaluation by a GI specialist. After a cumulative dose of 3.5 to 4 g, patients should receive a GI referral and further studies (such as vibration-controlled transient elastography or liver biopsy) to assess for liver fibrosis. Patients with signs of stage 3 liver fibrosis are recommended to discontinue methotrexate and switch to another medication for psoriasis. For patients with impaired renal function, periodic BUN and Cr monitoring are needed. Common adverse effects of methotrexate include diarrhea, nausea, and anorexia, which can be mitigated by taking methotrexate with food or lowering the dosage.⁸ Patients on methotrexate should be monitored for rare but potential risks of infection and reactivation of latent TB, hepatitis, and lymphoma. To reduce the incidence of methotrexate toxicity from drug interactions, a review of current medications at each follow-up visit is recommended.

Nephrotoxicity and hypertension are the most common adverse effects of cyclosporine. It is important to monitor BUN and Cr biweekly for the initial 3 months, then at monthly intervals if there are no persistent abnormalities. Patients also must receive monthly CBC, potassium and magnesium levels, uric acid levels, lipid panel, serum bilirubin, and LFTs to monitor for adverse effects.¹⁷ Physicians should obtain regular pregnancy tests in WOCP. Weekly monitoring of early-morning blood pressure is recommended for patients on cyclosporine to detect early cyclosporine-induced nephrotoxicity. Hypertension on 2 separate occasions warrants a reduction in cyclosporine dosage or an addition of a calcium channel blocker for blood pressure control. Dose reduction also should be performed in patients with an increase in Cr above baseline greater than 25%.¹⁷ If Cr level is persistently elevated or if blood pressure does not normalize to lower than 140/90 after dose reduction, cyclosporine should be immediately discontinued. Patients on cyclosporine for more than a year warrant an annual estimation of glomerular filtration rate because of irreversible kidney damage associated with long-term use. A systematic review of patients treated with cyclosporine for more than 2 years found that at least 50% of patients experienced a 30% increase in Cr above baseline.¹⁸

Patients taking acitretin should be monitored for hyperlipidemia, the most common laboratory abnormality seen in 25% to 50% of patients.¹⁹ Fasting lipid panel and LFTs should be performed monthly for the initial 3 months on acitretin, then at 3-month intervals. Lifestyle changes should be encouraged to reduce hyperlipidemia, and fibrates may be given to treat elevated triglyceride levels, the most common type of hyperlipidemia seen with acitretin. Acitretin-induced toxic hepatitis is a rare occurrence that warrants immediate discontinuation of the medication.²⁰ Monthly pregnancy tests must be performed in WOCP.

Combination Therapy

For apremilast, there is anecdotal evidence supporting its use in conjunction with phototherapy or biologics in some cases, but no high-quality data.²¹ On the other hand, using combination therapy with other systemic therapies can reduce adverse effects and decrease the amount of medication needed to achieve psoriasis clearance. Methotrexate used with etanercept, for example, has been more effective than methotrexate monotherapy in treating psoriasis, which has been attributed to a methotrexate-mediated reduction in the production of antidrug antibodies.^22,23

Methotrexate, cyclosporine, and acitretin have synergistic effects when used with phototherapy. Narrowband UVB (NB-UVB) phototherapy combined with methotrexate is more effective in clearing psoriasis than methotrexate or NB-UVB phototherapy alone. Similarly, acitretin and PUVA combination therapy is more effective than acitretin or PUVA phototherapy alone. Combination regimens of acitretin and broadband UVB phototherapy, acitretin and NB-UVB phototherapy, and acitretin and PUVA phototherapy also have been more effective than individual modalities alone. Combination therapy reduces the cumulative doses of both therapies and reduces the frequency and duration of phototherapy needed for psoriatic clearance.²⁴ In acitretin combination therapy with UVB phototherapy, the recommended regimen is 2 weeks of acitretin monotherapy followed by UVB phototherapy. For patients with an inadequate response to UVB phototherapy, the UVB dose can be reduced by 30% to 50%, and acitretin 25 mg/d can be added to phototherapy treatment. Acitretin-UVB combination therapy has been shown to reduce the risk of UVB-induced erythema seen in UVB monotherapy. Similarly, the risk of squamous cell carcinoma is reduced in acitretin-PUVA combination therapy compared to PUVA monotherapy.²⁵

The timing of phototherapy in combination with systemic nonbiologic agents is critical. Phototherapy used simultaneously with cyclosporine is contraindicated owing to increased risk of photocarcinogenesis, whereas phototherapy used in sequence with cyclosporine is well tolerated and effective. Furthermore, cyclosporine 3 mg/kg/d for 4 weeks followed by a rapid cyclosporine taper and initiation of NB-UVB phototherapy demonstrated resolution of psoriasis with fewer NB-UVB treatments and less UVB exposure than NB-UVB therapy alone.²⁶

Final Thoughts

The FDA-approved systemic nonbiologic agents are accessible and effective treatment options for adults with widespread or inadequately controlled psoriasis. Selecting the ideal therapy requires careful consideration of medication toxicity, contraindications, monitoring requirements, and patient comorbidities. The AAD-NPF guidelines guide dermatologists in prescribing systemic nonbiologic treatments in adults with psoriasis. Utilizing these recommendations in combination with clinician judgment will help patients achieve safe and optimal psoriasis clearance.