TBD Meeting (3270-20)

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

The investigational drug asciminib (being developed by Novartis) may become the new kid on the block for the treatment of chronic phase chronic myeloid leukemia (CMP-CP) for patients who have relapsed on or are refractory to at least two prior tyrosine kinase inhibitors (TKIs).

New results from the ASCEMBL study (NCT03106779) show that patients who received asciminib, which works differently from currently approved therapies for CML-CP, achieved better responses, compared with bosutinib (Bosulif) as third-line therapy.

“The ASCEMBL study opens a new chapter for CML, proving comparatively superior efficacy and excellent safety for a new class of ABL inhibitors,” coinvestigator Michael J. Mauro, MD, from Memorial Sloan Kettering Cancer Center, New York, said in an interview.

The trial was presented as a late-breaking abstract at the annual meeting of the American Society of Hematology.

Asciminib is a first-of-a-kind STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor that works differently from currently approved TKIs, which are adenosine triphosphate (ATP)-–competitive ABL inhibitors.

Five TKIs have been approved by the Food and Drug Administration to treat CML: imatinib (Gleevec; generics), nilotinib (Tasigna), dasatinib (Sprycel), bosutinib, and ponatinib (Iclusig).

All of them inhibit BCR/ABL tyrosine kinase by binding to the ATP-binding pocket.

Most patients with TKI resistant disease develop mutations in the ATP-binding pocket, explained Michael Jay Styler, MD, associate professor at Fox Chase–Temple University Hospital bone marrow transplant program, Fox Chase Cancer Center, Philadelphia.

By inactivating the protein through binding outside the ATP site, asciminib is a novel BCR-ABL inhibitor and may be a superior alternative to further traditional TKIs. “This agent promises to be an important addition to our treatment armamentarium for CML,” Dr. Styler said in an interview.

Another expert agreed. “Although we have many excellent therapies for CML, having a new medication that targets BCR-ABL in a novel way is still welcome to help us better care for CML patients,” Gabriela S. Hobbs, MD, said in an interview. Dr. Hobbs is the clinical director of leukemia services at Boston’s Mass General Cancer Center.

Patients in this study had previously been receiving at least two different types of TKIs. “The responses looked very encouraging for this group of heavily pretreated patients. Although CML patients do very well on current therapies, those that don’t get a response with TKI remain a difficult clinical challenge,” Dr. Hobbs said.

“This is the first study comparing asciminib to a TKI directly (in this case bosutinib) and it showed safety as well as preliminary evidence of efficacy. I look forward to seeing additional studies with this promising drug and to have a new drug to add to the CML arsenal,” she added.
 

Identifying patients who will benefit from asciminib

Patients with CML are currently sequenced through more than one second-generation TKI, Dr. Mauro commented. “If imatinib and a second-generation TKI have not served a patient well, only bosutinib has been studied in the third line and comparatively in the ASCEMBL study.” Asciminib was shown to be superior and could offer a clear alternative to ponatinib, which would be the other choice and is typically given even later after sequencing all other available options.

Dr. Hobbs agreed. “This is a challenging group of patients to manage as their options are limited. Ponatinib is often the drug of choice in these scenarios, as well as bone marrow transplant.”

Asciminib is not approved yet, but both Dr. Mauro and Dr. Hobbs are hopeful it will be by early next year, and that initial approval is likely in patients with CML-CP after several (two or three) lines of therapy. They also agreed that it may be effective (alone or in combination) in treating patients with T315I-mutation CML, which is a particularly challenging disease.

Senior study author Andreas Hochhaus, MD, of the Klinik für Innere Medizin II in Jena, Germany, who presented the data at the meeting, noted new trials to test the efficacy of asciminib alone or in combination in earlier lines of therapy are ongoing and include the investigator-initiated FASCINATION study (first-line asciminib in combination) in Germany (NCT03906292).
 

ASCEMBL study details

ASCEMBL is a phase 3 study in which patients with CML who had received at least two previous TKIs were randomized to asciminib (n = 157) 40 mg twice daily or bosutinib (n = 76) 500 mg once daily. In a protocol amendment, patients with documented failure on bosutinib were allowed to switch to asciminib.

The main reason for discontinuing the last TKI therapy was lack of efficacy in approximately two-thirds of patients. More patients in the asciminib than the bosutinib group received two prior lines of therapy (52% vs. 40%); the others had received three or more prior lines of therapy.

Median follow-up for the data cutoff was 14.9 months.

Dr. Hochhaus reported that treatment discontinuation was lower in patients receiving asciminib than bosutinib (38% vs. 70%) and was mostly due to lack of efficacy (21% vs. 32%) or adverse events (5% vs. 21%).

The study met its primary endpoint: major molecular response (MMR) was approximately twice as high with asciminib than bosutinib at 24 weeks (25.5% vs. 13.2%; P = .029). Treatment effect for MMR was 12.2%. Median duration of exposure to asciminib was 43.4 weeks for asciminib and 29.2 weeks for bosutinib.

“Consistent treatment effect was seen across all subgroups of patients, and MMR rates were consistently high for patients on asciminib across all prior lines of therapy,” Dr. Hochhaus reported.

The probability of achieving MMR at 24 weeks was higher for patients receiving asciminib (25% vs. 11.9%) and started at week 12, he noted. Complete cytogenetic response was also higher for patients receiving asciminib (40.8% vs. 24.2%).

The occurrence of grade 3 or higher adverse events was lower with asciminib than bosutinib (51% vs. 61%). Thrombocytopenia and neutropenia were more common with asciminib and gastrointestinal events were more common with bosutinib. Arterial occlusion events were reported in five patients receiving asciminib and one patient receiving bosutinib. Most of these patients had prior exposure to imatinib, nilotinib, and/or dasatinib.

Dr. Mauro, a coinvestigator of the phase 3 study, also treated patients with the drug in the phase 1 study. “I feel asciminib has proven to be very well tolerated, with rare to absent cases of intolerance,” he said. Cardiovascular and cardiopulmonary adverse events are exceedingly rare as well.

Longer follow-up of the ASCEMBL study and continued follow-up of the myriad of groups from the phase 1 trial (T315I-positive patients treated with higher-dose asciminib, combination therapy with imatinib/nilotinib/dasatinib plus asciminib, and others) will be essential to settle any questions regarding selective adverse events of interest such as vascular occlusion, Dr. Mauro noted.

Dr. Hochhaus has reported receiving research funding from Novartis, Incyte, Pfizer, and Bristol-Myers Squibb. Dr. Hobbs has reported serving on advisory boards for Novartis. Dr. Mauro has reported financial relationships with Bristol-Myers Squibb, Novartis, Takeda, Pfizer, and Sun Pharma/SPARC.

A version of this article first appeared on Medscape.com.

The investigational drug asciminib (being developed by Novartis) may become the new kid on the block for the treatment of chronic phase chronic myeloid leukemia (CMP-CP) for patients who have relapsed on or are refractory to at least two prior tyrosine kinase inhibitors (TKIs).

New results from the ASCEMBL study (NCT03106779) show that patients who received asciminib, which works differently from currently approved therapies for CML-CP, achieved better responses, compared with bosutinib (Bosulif) as third-line therapy.

“The ASCEMBL study opens a new chapter for CML, proving comparatively superior efficacy and excellent safety for a new class of ABL inhibitors,” coinvestigator Michael J. Mauro, MD, from Memorial Sloan Kettering Cancer Center, New York, said in an interview.

The trial was presented as a late-breaking abstract at the annual meeting of the American Society of Hematology.

Asciminib is a first-of-a-kind STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor that works differently from currently approved TKIs, which are adenosine triphosphate (ATP)-–competitive ABL inhibitors.

Five TKIs have been approved by the Food and Drug Administration to treat CML: imatinib (Gleevec; generics), nilotinib (Tasigna), dasatinib (Sprycel), bosutinib, and ponatinib (Iclusig).

All of them inhibit BCR/ABL tyrosine kinase by binding to the ATP-binding pocket.

Most patients with TKI resistant disease develop mutations in the ATP-binding pocket, explained Michael Jay Styler, MD, associate professor at Fox Chase–Temple University Hospital bone marrow transplant program, Fox Chase Cancer Center, Philadelphia.

By inactivating the protein through binding outside the ATP site, asciminib is a novel BCR-ABL inhibitor and may be a superior alternative to further traditional TKIs. “This agent promises to be an important addition to our treatment armamentarium for CML,” Dr. Styler said in an interview.

Another expert agreed. “Although we have many excellent therapies for CML, having a new medication that targets BCR-ABL in a novel way is still welcome to help us better care for CML patients,” Gabriela S. Hobbs, MD, said in an interview. Dr. Hobbs is the clinical director of leukemia services at Boston’s Mass General Cancer Center.

Patients in this study had previously been receiving at least two different types of TKIs. “The responses looked very encouraging for this group of heavily pretreated patients. Although CML patients do very well on current therapies, those that don’t get a response with TKI remain a difficult clinical challenge,” Dr. Hobbs said.

“This is the first study comparing asciminib to a TKI directly (in this case bosutinib) and it showed safety as well as preliminary evidence of efficacy. I look forward to seeing additional studies with this promising drug and to have a new drug to add to the CML arsenal,” she added.
 

Identifying patients who will benefit from asciminib

Patients with CML are currently sequenced through more than one second-generation TKI, Dr. Mauro commented. “If imatinib and a second-generation TKI have not served a patient well, only bosutinib has been studied in the third line and comparatively in the ASCEMBL study.” Asciminib was shown to be superior and could offer a clear alternative to ponatinib, which would be the other choice and is typically given even later after sequencing all other available options.

Dr. Hobbs agreed. “This is a challenging group of patients to manage as their options are limited. Ponatinib is often the drug of choice in these scenarios, as well as bone marrow transplant.”

Asciminib is not approved yet, but both Dr. Mauro and Dr. Hobbs are hopeful it will be by early next year, and that initial approval is likely in patients with CML-CP after several (two or three) lines of therapy. They also agreed that it may be effective (alone or in combination) in treating patients with T315I-mutation CML, which is a particularly challenging disease.

Senior study author Andreas Hochhaus, MD, of the Klinik für Innere Medizin II in Jena, Germany, who presented the data at the meeting, noted new trials to test the efficacy of asciminib alone or in combination in earlier lines of therapy are ongoing and include the investigator-initiated FASCINATION study (first-line asciminib in combination) in Germany (NCT03906292).
 

ASCEMBL study details

ASCEMBL is a phase 3 study in which patients with CML who had received at least two previous TKIs were randomized to asciminib (n = 157) 40 mg twice daily or bosutinib (n = 76) 500 mg once daily. In a protocol amendment, patients with documented failure on bosutinib were allowed to switch to asciminib.

The main reason for discontinuing the last TKI therapy was lack of efficacy in approximately two-thirds of patients. More patients in the asciminib than the bosutinib group received two prior lines of therapy (52% vs. 40%); the others had received three or more prior lines of therapy.

Median follow-up for the data cutoff was 14.9 months.

Dr. Hochhaus reported that treatment discontinuation was lower in patients receiving asciminib than bosutinib (38% vs. 70%) and was mostly due to lack of efficacy (21% vs. 32%) or adverse events (5% vs. 21%).

The study met its primary endpoint: major molecular response (MMR) was approximately twice as high with asciminib than bosutinib at 24 weeks (25.5% vs. 13.2%; P = .029). Treatment effect for MMR was 12.2%. Median duration of exposure to asciminib was 43.4 weeks for asciminib and 29.2 weeks for bosutinib.

“Consistent treatment effect was seen across all subgroups of patients, and MMR rates were consistently high for patients on asciminib across all prior lines of therapy,” Dr. Hochhaus reported.

The probability of achieving MMR at 24 weeks was higher for patients receiving asciminib (25% vs. 11.9%) and started at week 12, he noted. Complete cytogenetic response was also higher for patients receiving asciminib (40.8% vs. 24.2%).

The occurrence of grade 3 or higher adverse events was lower with asciminib than bosutinib (51% vs. 61%). Thrombocytopenia and neutropenia were more common with asciminib and gastrointestinal events were more common with bosutinib. Arterial occlusion events were reported in five patients receiving asciminib and one patient receiving bosutinib. Most of these patients had prior exposure to imatinib, nilotinib, and/or dasatinib.

Dr. Mauro, a coinvestigator of the phase 3 study, also treated patients with the drug in the phase 1 study. “I feel asciminib has proven to be very well tolerated, with rare to absent cases of intolerance,” he said. Cardiovascular and cardiopulmonary adverse events are exceedingly rare as well.

Longer follow-up of the ASCEMBL study and continued follow-up of the myriad of groups from the phase 1 trial (T315I-positive patients treated with higher-dose asciminib, combination therapy with imatinib/nilotinib/dasatinib plus asciminib, and others) will be essential to settle any questions regarding selective adverse events of interest such as vascular occlusion, Dr. Mauro noted.

Dr. Hochhaus has reported receiving research funding from Novartis, Incyte, Pfizer, and Bristol-Myers Squibb. Dr. Hobbs has reported serving on advisory boards for Novartis. Dr. Mauro has reported financial relationships with Bristol-Myers Squibb, Novartis, Takeda, Pfizer, and Sun Pharma/SPARC.

A version of this article first appeared on Medscape.com.

The investigational drug asciminib (being developed by Novartis) may become the new kid on the block for the treatment of chronic phase chronic myeloid leukemia (CMP-CP) for patients who have relapsed on or are refractory to at least two prior tyrosine kinase inhibitors (TKIs).

New results from the ASCEMBL study (NCT03106779) show that patients who received asciminib, which works differently from currently approved therapies for CML-CP, achieved better responses, compared with bosutinib (Bosulif) as third-line therapy.

“The ASCEMBL study opens a new chapter for CML, proving comparatively superior efficacy and excellent safety for a new class of ABL inhibitors,” coinvestigator Michael J. Mauro, MD, from Memorial Sloan Kettering Cancer Center, New York, said in an interview.

The trial was presented as a late-breaking abstract at the annual meeting of the American Society of Hematology.

Asciminib is a first-of-a-kind STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor that works differently from currently approved TKIs, which are adenosine triphosphate (ATP)-–competitive ABL inhibitors.

Five TKIs have been approved by the Food and Drug Administration to treat CML: imatinib (Gleevec; generics), nilotinib (Tasigna), dasatinib (Sprycel), bosutinib, and ponatinib (Iclusig).

All of them inhibit BCR/ABL tyrosine kinase by binding to the ATP-binding pocket.

Most patients with TKI resistant disease develop mutations in the ATP-binding pocket, explained Michael Jay Styler, MD, associate professor at Fox Chase–Temple University Hospital bone marrow transplant program, Fox Chase Cancer Center, Philadelphia.

By inactivating the protein through binding outside the ATP site, asciminib is a novel BCR-ABL inhibitor and may be a superior alternative to further traditional TKIs. “This agent promises to be an important addition to our treatment armamentarium for CML,” Dr. Styler said in an interview.

Another expert agreed. “Although we have many excellent therapies for CML, having a new medication that targets BCR-ABL in a novel way is still welcome to help us better care for CML patients,” Gabriela S. Hobbs, MD, said in an interview. Dr. Hobbs is the clinical director of leukemia services at Boston’s Mass General Cancer Center.

Patients in this study had previously been receiving at least two different types of TKIs. “The responses looked very encouraging for this group of heavily pretreated patients. Although CML patients do very well on current therapies, those that don’t get a response with TKI remain a difficult clinical challenge,” Dr. Hobbs said.

“This is the first study comparing asciminib to a TKI directly (in this case bosutinib) and it showed safety as well as preliminary evidence of efficacy. I look forward to seeing additional studies with this promising drug and to have a new drug to add to the CML arsenal,” she added.
 

Identifying patients who will benefit from asciminib

Patients with CML are currently sequenced through more than one second-generation TKI, Dr. Mauro commented. “If imatinib and a second-generation TKI have not served a patient well, only bosutinib has been studied in the third line and comparatively in the ASCEMBL study.” Asciminib was shown to be superior and could offer a clear alternative to ponatinib, which would be the other choice and is typically given even later after sequencing all other available options.

Dr. Hobbs agreed. “This is a challenging group of patients to manage as their options are limited. Ponatinib is often the drug of choice in these scenarios, as well as bone marrow transplant.”

Asciminib is not approved yet, but both Dr. Mauro and Dr. Hobbs are hopeful it will be by early next year, and that initial approval is likely in patients with CML-CP after several (two or three) lines of therapy. They also agreed that it may be effective (alone or in combination) in treating patients with T315I-mutation CML, which is a particularly challenging disease.

Senior study author Andreas Hochhaus, MD, of the Klinik für Innere Medizin II in Jena, Germany, who presented the data at the meeting, noted new trials to test the efficacy of asciminib alone or in combination in earlier lines of therapy are ongoing and include the investigator-initiated FASCINATION study (first-line asciminib in combination) in Germany (NCT03906292).
 

ASCEMBL study details

ASCEMBL is a phase 3 study in which patients with CML who had received at least two previous TKIs were randomized to asciminib (n = 157) 40 mg twice daily or bosutinib (n = 76) 500 mg once daily. In a protocol amendment, patients with documented failure on bosutinib were allowed to switch to asciminib.

The main reason for discontinuing the last TKI therapy was lack of efficacy in approximately two-thirds of patients. More patients in the asciminib than the bosutinib group received two prior lines of therapy (52% vs. 40%); the others had received three or more prior lines of therapy.

Median follow-up for the data cutoff was 14.9 months.

Dr. Hochhaus reported that treatment discontinuation was lower in patients receiving asciminib than bosutinib (38% vs. 70%) and was mostly due to lack of efficacy (21% vs. 32%) or adverse events (5% vs. 21%).

The study met its primary endpoint: major molecular response (MMR) was approximately twice as high with asciminib than bosutinib at 24 weeks (25.5% vs. 13.2%; P = .029). Treatment effect for MMR was 12.2%. Median duration of exposure to asciminib was 43.4 weeks for asciminib and 29.2 weeks for bosutinib.

“Consistent treatment effect was seen across all subgroups of patients, and MMR rates were consistently high for patients on asciminib across all prior lines of therapy,” Dr. Hochhaus reported.

The probability of achieving MMR at 24 weeks was higher for patients receiving asciminib (25% vs. 11.9%) and started at week 12, he noted. Complete cytogenetic response was also higher for patients receiving asciminib (40.8% vs. 24.2%).

The occurrence of grade 3 or higher adverse events was lower with asciminib than bosutinib (51% vs. 61%). Thrombocytopenia and neutropenia were more common with asciminib and gastrointestinal events were more common with bosutinib. Arterial occlusion events were reported in five patients receiving asciminib and one patient receiving bosutinib. Most of these patients had prior exposure to imatinib, nilotinib, and/or dasatinib.

Dr. Mauro, a coinvestigator of the phase 3 study, also treated patients with the drug in the phase 1 study. “I feel asciminib has proven to be very well tolerated, with rare to absent cases of intolerance,” he said. Cardiovascular and cardiopulmonary adverse events are exceedingly rare as well.

Longer follow-up of the ASCEMBL study and continued follow-up of the myriad of groups from the phase 1 trial (T315I-positive patients treated with higher-dose asciminib, combination therapy with imatinib/nilotinib/dasatinib plus asciminib, and others) will be essential to settle any questions regarding selective adverse events of interest such as vascular occlusion, Dr. Mauro noted.

Dr. Hochhaus has reported receiving research funding from Novartis, Incyte, Pfizer, and Bristol-Myers Squibb. Dr. Hobbs has reported serving on advisory boards for Novartis. Dr. Mauro has reported financial relationships with Bristol-Myers Squibb, Novartis, Takeda, Pfizer, and Sun Pharma/SPARC.

A version of this article first appeared on Medscape.com.

A newly devised, validated prognostic tool – the Burkitt Lymphoma International Prognostic Index – can consistently identify low-risk patients who might benefit from treatment de-escalation, and high-risk patients who are unlikely to be cured with current therapies and may require novel approaches, investigators said.

In a cohort of patients treated at international sites, patients with a low-risk score on the BL-IPI had a 3-year progression-free survival (PFS) rate of 96%, and 3-year overall survival rate (OS) of 99%. In contrast, the 3-year PFS rate for patients in the high-risk category was 63%, and the 3-year OS rate was 64%, reported Adam J Olszewski, MD, from the Lifespan Cancer Institute at Rhode Island Hospital and The Miriam Hospital, both in Providence.

“The Burkitt Lymphoma International Prognostic Index – or the ‘BLI-PI’ [‘blippy’] as it was inevitably called – is a novel prognostic index that is specific to Burkitt lymphoma. It has been validated with sufficient calibration and discrimination in external data sets to allow for simple stratification and comparison of risk distribution in geographically diverse cohorts,” he said in an oral abstract presented virtually during the annual meeting of the American Society of Hematology.
 

Inconsistent criteria

There is a need for a Burkitt-specific index, he said, because of significant differences in age, stage at presentation, and abnormal lactate dehydrogenase (LDH) levels between patients with Burkitt and those with diffuse large B-cell lymphoma (DLBCL), and because historical definitions of “low-risk” Burkitt lymphoma have been inconsistent, with less than 10% of patients falling into this group, leaving the remainder in a undifferentiated “high-risk” category.

“Burkitt lymphoma is considered highly curable, but current therapy requires administration of dose-intense chemoimmunotherapy for which there are many chemotherapy backbone regimens developed across the world, and used mostly locally. These are often studied in phase 2 studies with limited sample sizes, which makes it difficult to compare populations across trials,” Dr. Olszewski said.

A validated prognostic index can help clinicians and researchers compare cohorts and can be used to help design future trials, he added.

To devise the BL-IPI, the investigators first selected a retrospective cohort of 570 adults with Burkitt lymphoma treated at 30 U.S. centers for whom data on outcomes were available.

They determined the best prognostic cutoffs for age, LDH, hemoglobin and albumin levels, and identified independent risk factors using stepwise selection in Cox regression and lasso regression analysis, a machine learning approach. The variables included age; sex; HIV-positivity status; loss of MYC rearrangement; performance status; stage; nodal involvement; marrow involvement; central nervous system involvement; and LDH, hemoglobin, and albumin levels.

For validation, they pooled data from European, Canadian, Australian, and U.K. studies to identify 457 patients for whom retrospective treatment and outcomes data were available.

The derivation and validation cohorts were similar in most respects, expect for a higher proportion of patients with Eastern Cooperative Oncology Group performance status scores of 2 or higher in the validation cohort (22% vs. 35%), and a higher proportion of patients with CNS involvement in the U.S.-based derivation cohort (19% vs. 10%, respectively).

Therapy also differed markedly between the U.S. and international cohorts, with about 30% each of U.S. patients receiving either the CODOX-M/IVAC (cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, and high-dose cytarabine) regimen, DA-EPOCH-R (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab) regimen, or hCVAD/MA (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high-dose methotrexate and cytarabine) regimen, and the remaining 10% receiving other, unspecified therapy.

In contrast, 65% of the patients in the international (validation) cohort received CODOX-M/IVAC, 10% and 9%, respectively, received DA-EPOCH-R and hCVAD/MA, and 16% receiving other regimens.

Rituximab was administered to 91% of U.S. and 95% of international patients.
 

Higher survival rates outside US

Both PFS and OS were higher in the international versus U.S. cohort. At a median follow-up of 45 months, the PFS rate in the United States was 65%, and the OS rate was 70%.

In the international cohort, after a median follow-up of 52 months, the PFS rate was 75%, and the OS rate was 76%, the investigators found.

Reasons for the differences may be because of differences in treatment regimens, socioeconomic and racial disparities in the United States versus other countries, or to decentralized Burkitt lymphoma therapy in the United States, Dr. Olszewski said.

In univariate analysis, factors significantly predictive of worse PFS included age 40 years or older, ECOG performance status 2 or greater, stage 3 or 4 disease, marrow involvement, CNS involvement, LDH more than three times the upper limit of normal, and hemoglobin <11.5 g/dL (P < .001 for all preceding), as well as albumin <3.5 g/dL (P = .001).

“However, the multivariable analysis was more complicated, because many of these factors were overlapping, and most patients with high LDH also had advanced disease, and this group also encompassed patients who had bone marrow and CNS involvement,” he said.

Using the two types of regression analysis mentioned before, investigators identified ECOG performance status 2 or greater (P = .001), age 40 and older (P = .005), LDH greater than three times the upper limit of normal (P < .001) and CNS involvement (P = .002) as significant predictors for worse outcomes in multivariable analysis, and were included in the final model.

“We initially had five groups according to the number of these factors, but we observed that the survival curves for patients with two, three, or four factors were overlapping, and not significantly different, so ultimately we had three risk groups. In the derivation (U.S.) cohort, patients in the low-risk group, with no risk factors, a 3-year PFS of 92%, compared with 72% for patients with one risk factor (intermediate risk), and 53% for patients with two to four risk factors (high risk).

Respective hazard ratios for worse PFS in the low-, intermediate-, and high-risk groups were 1 (reference), 4.15 (95% confidence interval, 1.99-8.68), and 8.83 (95% CI, 4.32-18.03).

Respective HR for worse OS was 1, 7.06 (95% CI, 2.55-19.53), and 15.12 (95% CI, 5.58-40.99).

There were no significant differences in either PFS or OS when either LDH or stage was added into the model.

The BL-IPI was prognostic for PFS and OS in all subgroups, including HIV-positive or -negative patients, those with MYC rearrangements, stage 1 or 2 versus stage 3 or 4, or those treated with rituximab versus those who were not.

As noted before, 3-year PFS rates in the validation cohort for low, intermediate, high-risk groups were 96%, 82%, and 63% respectively, and 3-year OS rates were 99%, 85%, and 64%.
 

Why the CNS discrepancy?

In the question and answer session following the presentation, comoderator Christopher J. Melani, MD, from the Lymphoid Malignancies Branch at the National Cancer Institute in Bethesda, Md., said that “it was interesting to see the difference between CNS involvement in both the U.S. and the international cohort,” and asked whether Dr. Olszweski could elaborate on whether baseline CNS involvement was assessed by contrast-enhanced MRI of flow cytometry studies of cerebrospinal fluid.

“Could some of these differences between the U.S. and the international cohort be from the baseline assessment differing between the two?” he asked.

Dr. Olszewski replied that the retrospective nature of the data precluded capturing those data, but added that “I do suspect there may be some differences in the way that central nervous system is staged in different countries. In the United States the use of flow cytometry is more commonly employed, but we don’t know how it is used internationally. We do not know how often this is staged radiographically.”

Asked by others who viewed the presentation whether extranodal disease or peripheral blood involvement were prognostic in the final model, Dr. Olszewski replied that “one has to understand that, when one constructs a prognostic index, there is a balance between trying to input as much information as possible and to create something that is useful, clinically meaningful, and accurate.”

He said that, despite trying different models with different factors, “we couldn’t get the discrimination to be much better than the basic model that we ultimately created, so we favored using a more parsimonious model.”

No study funding source was reported. Dr. Olszewski reported research funding from Spectrum Pharmaceuticals, Genentech, TG Therapeutics, and Adaptive Biotechnologies. Dr. Melani reported having no relevant conflicts of interest.

SOURCE: Olszewski AJ et al. ASH 2020, Abstract 705.

A newly devised, validated prognostic tool – the Burkitt Lymphoma International Prognostic Index – can consistently identify low-risk patients who might benefit from treatment de-escalation, and high-risk patients who are unlikely to be cured with current therapies and may require novel approaches, investigators said.

In a cohort of patients treated at international sites, patients with a low-risk score on the BL-IPI had a 3-year progression-free survival (PFS) rate of 96%, and 3-year overall survival rate (OS) of 99%. In contrast, the 3-year PFS rate for patients in the high-risk category was 63%, and the 3-year OS rate was 64%, reported Adam J Olszewski, MD, from the Lifespan Cancer Institute at Rhode Island Hospital and The Miriam Hospital, both in Providence.

“The Burkitt Lymphoma International Prognostic Index – or the ‘BLI-PI’ [‘blippy’] as it was inevitably called – is a novel prognostic index that is specific to Burkitt lymphoma. It has been validated with sufficient calibration and discrimination in external data sets to allow for simple stratification and comparison of risk distribution in geographically diverse cohorts,” he said in an oral abstract presented virtually during the annual meeting of the American Society of Hematology.
 

Inconsistent criteria

There is a need for a Burkitt-specific index, he said, because of significant differences in age, stage at presentation, and abnormal lactate dehydrogenase (LDH) levels between patients with Burkitt and those with diffuse large B-cell lymphoma (DLBCL), and because historical definitions of “low-risk” Burkitt lymphoma have been inconsistent, with less than 10% of patients falling into this group, leaving the remainder in a undifferentiated “high-risk” category.

“Burkitt lymphoma is considered highly curable, but current therapy requires administration of dose-intense chemoimmunotherapy for which there are many chemotherapy backbone regimens developed across the world, and used mostly locally. These are often studied in phase 2 studies with limited sample sizes, which makes it difficult to compare populations across trials,” Dr. Olszewski said.

A validated prognostic index can help clinicians and researchers compare cohorts and can be used to help design future trials, he added.

To devise the BL-IPI, the investigators first selected a retrospective cohort of 570 adults with Burkitt lymphoma treated at 30 U.S. centers for whom data on outcomes were available.

They determined the best prognostic cutoffs for age, LDH, hemoglobin and albumin levels, and identified independent risk factors using stepwise selection in Cox regression and lasso regression analysis, a machine learning approach. The variables included age; sex; HIV-positivity status; loss of MYC rearrangement; performance status; stage; nodal involvement; marrow involvement; central nervous system involvement; and LDH, hemoglobin, and albumin levels.

For validation, they pooled data from European, Canadian, Australian, and U.K. studies to identify 457 patients for whom retrospective treatment and outcomes data were available.

The derivation and validation cohorts were similar in most respects, expect for a higher proportion of patients with Eastern Cooperative Oncology Group performance status scores of 2 or higher in the validation cohort (22% vs. 35%), and a higher proportion of patients with CNS involvement in the U.S.-based derivation cohort (19% vs. 10%, respectively).

Therapy also differed markedly between the U.S. and international cohorts, with about 30% each of U.S. patients receiving either the CODOX-M/IVAC (cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, and high-dose cytarabine) regimen, DA-EPOCH-R (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab) regimen, or hCVAD/MA (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high-dose methotrexate and cytarabine) regimen, and the remaining 10% receiving other, unspecified therapy.

In contrast, 65% of the patients in the international (validation) cohort received CODOX-M/IVAC, 10% and 9%, respectively, received DA-EPOCH-R and hCVAD/MA, and 16% receiving other regimens.

Rituximab was administered to 91% of U.S. and 95% of international patients.
 

Higher survival rates outside US

Both PFS and OS were higher in the international versus U.S. cohort. At a median follow-up of 45 months, the PFS rate in the United States was 65%, and the OS rate was 70%.

In the international cohort, after a median follow-up of 52 months, the PFS rate was 75%, and the OS rate was 76%, the investigators found.

Reasons for the differences may be because of differences in treatment regimens, socioeconomic and racial disparities in the United States versus other countries, or to decentralized Burkitt lymphoma therapy in the United States, Dr. Olszewski said.

In univariate analysis, factors significantly predictive of worse PFS included age 40 years or older, ECOG performance status 2 or greater, stage 3 or 4 disease, marrow involvement, CNS involvement, LDH more than three times the upper limit of normal, and hemoglobin <11.5 g/dL (P < .001 for all preceding), as well as albumin <3.5 g/dL (P = .001).

“However, the multivariable analysis was more complicated, because many of these factors were overlapping, and most patients with high LDH also had advanced disease, and this group also encompassed patients who had bone marrow and CNS involvement,” he said.

Using the two types of regression analysis mentioned before, investigators identified ECOG performance status 2 or greater (P = .001), age 40 and older (P = .005), LDH greater than three times the upper limit of normal (P < .001) and CNS involvement (P = .002) as significant predictors for worse outcomes in multivariable analysis, and were included in the final model.

“We initially had five groups according to the number of these factors, but we observed that the survival curves for patients with two, three, or four factors were overlapping, and not significantly different, so ultimately we had three risk groups. In the derivation (U.S.) cohort, patients in the low-risk group, with no risk factors, a 3-year PFS of 92%, compared with 72% for patients with one risk factor (intermediate risk), and 53% for patients with two to four risk factors (high risk).

Respective hazard ratios for worse PFS in the low-, intermediate-, and high-risk groups were 1 (reference), 4.15 (95% confidence interval, 1.99-8.68), and 8.83 (95% CI, 4.32-18.03).

Respective HR for worse OS was 1, 7.06 (95% CI, 2.55-19.53), and 15.12 (95% CI, 5.58-40.99).

There were no significant differences in either PFS or OS when either LDH or stage was added into the model.

The BL-IPI was prognostic for PFS and OS in all subgroups, including HIV-positive or -negative patients, those with MYC rearrangements, stage 1 or 2 versus stage 3 or 4, or those treated with rituximab versus those who were not.

As noted before, 3-year PFS rates in the validation cohort for low, intermediate, high-risk groups were 96%, 82%, and 63% respectively, and 3-year OS rates were 99%, 85%, and 64%.
 

Why the CNS discrepancy?

In the question and answer session following the presentation, comoderator Christopher J. Melani, MD, from the Lymphoid Malignancies Branch at the National Cancer Institute in Bethesda, Md., said that “it was interesting to see the difference between CNS involvement in both the U.S. and the international cohort,” and asked whether Dr. Olszweski could elaborate on whether baseline CNS involvement was assessed by contrast-enhanced MRI of flow cytometry studies of cerebrospinal fluid.

“Could some of these differences between the U.S. and the international cohort be from the baseline assessment differing between the two?” he asked.

Dr. Olszewski replied that the retrospective nature of the data precluded capturing those data, but added that “I do suspect there may be some differences in the way that central nervous system is staged in different countries. In the United States the use of flow cytometry is more commonly employed, but we don’t know how it is used internationally. We do not know how often this is staged radiographically.”

Asked by others who viewed the presentation whether extranodal disease or peripheral blood involvement were prognostic in the final model, Dr. Olszewski replied that “one has to understand that, when one constructs a prognostic index, there is a balance between trying to input as much information as possible and to create something that is useful, clinically meaningful, and accurate.”

He said that, despite trying different models with different factors, “we couldn’t get the discrimination to be much better than the basic model that we ultimately created, so we favored using a more parsimonious model.”

No study funding source was reported. Dr. Olszewski reported research funding from Spectrum Pharmaceuticals, Genentech, TG Therapeutics, and Adaptive Biotechnologies. Dr. Melani reported having no relevant conflicts of interest.

SOURCE: Olszewski AJ et al. ASH 2020, Abstract 705.

A newly devised, validated prognostic tool – the Burkitt Lymphoma International Prognostic Index – can consistently identify low-risk patients who might benefit from treatment de-escalation, and high-risk patients who are unlikely to be cured with current therapies and may require novel approaches, investigators said.

In a cohort of patients treated at international sites, patients with a low-risk score on the BL-IPI had a 3-year progression-free survival (PFS) rate of 96%, and 3-year overall survival rate (OS) of 99%. In contrast, the 3-year PFS rate for patients in the high-risk category was 63%, and the 3-year OS rate was 64%, reported Adam J Olszewski, MD, from the Lifespan Cancer Institute at Rhode Island Hospital and The Miriam Hospital, both in Providence.

“The Burkitt Lymphoma International Prognostic Index – or the ‘BLI-PI’ [‘blippy’] as it was inevitably called – is a novel prognostic index that is specific to Burkitt lymphoma. It has been validated with sufficient calibration and discrimination in external data sets to allow for simple stratification and comparison of risk distribution in geographically diverse cohorts,” he said in an oral abstract presented virtually during the annual meeting of the American Society of Hematology.
 

Inconsistent criteria

There is a need for a Burkitt-specific index, he said, because of significant differences in age, stage at presentation, and abnormal lactate dehydrogenase (LDH) levels between patients with Burkitt and those with diffuse large B-cell lymphoma (DLBCL), and because historical definitions of “low-risk” Burkitt lymphoma have been inconsistent, with less than 10% of patients falling into this group, leaving the remainder in a undifferentiated “high-risk” category.

“Burkitt lymphoma is considered highly curable, but current therapy requires administration of dose-intense chemoimmunotherapy for which there are many chemotherapy backbone regimens developed across the world, and used mostly locally. These are often studied in phase 2 studies with limited sample sizes, which makes it difficult to compare populations across trials,” Dr. Olszewski said.

A validated prognostic index can help clinicians and researchers compare cohorts and can be used to help design future trials, he added.

To devise the BL-IPI, the investigators first selected a retrospective cohort of 570 adults with Burkitt lymphoma treated at 30 U.S. centers for whom data on outcomes were available.

They determined the best prognostic cutoffs for age, LDH, hemoglobin and albumin levels, and identified independent risk factors using stepwise selection in Cox regression and lasso regression analysis, a machine learning approach. The variables included age; sex; HIV-positivity status; loss of MYC rearrangement; performance status; stage; nodal involvement; marrow involvement; central nervous system involvement; and LDH, hemoglobin, and albumin levels.

For validation, they pooled data from European, Canadian, Australian, and U.K. studies to identify 457 patients for whom retrospective treatment and outcomes data were available.

The derivation and validation cohorts were similar in most respects, expect for a higher proportion of patients with Eastern Cooperative Oncology Group performance status scores of 2 or higher in the validation cohort (22% vs. 35%), and a higher proportion of patients with CNS involvement in the U.S.-based derivation cohort (19% vs. 10%, respectively).

Therapy also differed markedly between the U.S. and international cohorts, with about 30% each of U.S. patients receiving either the CODOX-M/IVAC (cyclophosphamide, vincristine, doxorubicin, high-dose methotrexate/ifosfamide, etoposide, and high-dose cytarabine) regimen, DA-EPOCH-R (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab) regimen, or hCVAD/MA (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone alternating with high-dose methotrexate and cytarabine) regimen, and the remaining 10% receiving other, unspecified therapy.

In contrast, 65% of the patients in the international (validation) cohort received CODOX-M/IVAC, 10% and 9%, respectively, received DA-EPOCH-R and hCVAD/MA, and 16% receiving other regimens.

Rituximab was administered to 91% of U.S. and 95% of international patients.
 

Higher survival rates outside US

Both PFS and OS were higher in the international versus U.S. cohort. At a median follow-up of 45 months, the PFS rate in the United States was 65%, and the OS rate was 70%.

In the international cohort, after a median follow-up of 52 months, the PFS rate was 75%, and the OS rate was 76%, the investigators found.

Reasons for the differences may be because of differences in treatment regimens, socioeconomic and racial disparities in the United States versus other countries, or to decentralized Burkitt lymphoma therapy in the United States, Dr. Olszewski said.

In univariate analysis, factors significantly predictive of worse PFS included age 40 years or older, ECOG performance status 2 or greater, stage 3 or 4 disease, marrow involvement, CNS involvement, LDH more than three times the upper limit of normal, and hemoglobin <11.5 g/dL (P < .001 for all preceding), as well as albumin <3.5 g/dL (P = .001).

“However, the multivariable analysis was more complicated, because many of these factors were overlapping, and most patients with high LDH also had advanced disease, and this group also encompassed patients who had bone marrow and CNS involvement,” he said.

Using the two types of regression analysis mentioned before, investigators identified ECOG performance status 2 or greater (P = .001), age 40 and older (P = .005), LDH greater than three times the upper limit of normal (P < .001) and CNS involvement (P = .002) as significant predictors for worse outcomes in multivariable analysis, and were included in the final model.

“We initially had five groups according to the number of these factors, but we observed that the survival curves for patients with two, three, or four factors were overlapping, and not significantly different, so ultimately we had three risk groups. In the derivation (U.S.) cohort, patients in the low-risk group, with no risk factors, a 3-year PFS of 92%, compared with 72% for patients with one risk factor (intermediate risk), and 53% for patients with two to four risk factors (high risk).

Respective hazard ratios for worse PFS in the low-, intermediate-, and high-risk groups were 1 (reference), 4.15 (95% confidence interval, 1.99-8.68), and 8.83 (95% CI, 4.32-18.03).

Respective HR for worse OS was 1, 7.06 (95% CI, 2.55-19.53), and 15.12 (95% CI, 5.58-40.99).

There were no significant differences in either PFS or OS when either LDH or stage was added into the model.

The BL-IPI was prognostic for PFS and OS in all subgroups, including HIV-positive or -negative patients, those with MYC rearrangements, stage 1 or 2 versus stage 3 or 4, or those treated with rituximab versus those who were not.

As noted before, 3-year PFS rates in the validation cohort for low, intermediate, high-risk groups were 96%, 82%, and 63% respectively, and 3-year OS rates were 99%, 85%, and 64%.
 

Why the CNS discrepancy?

In the question and answer session following the presentation, comoderator Christopher J. Melani, MD, from the Lymphoid Malignancies Branch at the National Cancer Institute in Bethesda, Md., said that “it was interesting to see the difference between CNS involvement in both the U.S. and the international cohort,” and asked whether Dr. Olszweski could elaborate on whether baseline CNS involvement was assessed by contrast-enhanced MRI of flow cytometry studies of cerebrospinal fluid.

“Could some of these differences between the U.S. and the international cohort be from the baseline assessment differing between the two?” he asked.

Dr. Olszewski replied that the retrospective nature of the data precluded capturing those data, but added that “I do suspect there may be some differences in the way that central nervous system is staged in different countries. In the United States the use of flow cytometry is more commonly employed, but we don’t know how it is used internationally. We do not know how often this is staged radiographically.”

Asked by others who viewed the presentation whether extranodal disease or peripheral blood involvement were prognostic in the final model, Dr. Olszewski replied that “one has to understand that, when one constructs a prognostic index, there is a balance between trying to input as much information as possible and to create something that is useful, clinically meaningful, and accurate.”

He said that, despite trying different models with different factors, “we couldn’t get the discrimination to be much better than the basic model that we ultimately created, so we favored using a more parsimonious model.”

No study funding source was reported. Dr. Olszewski reported research funding from Spectrum Pharmaceuticals, Genentech, TG Therapeutics, and Adaptive Biotechnologies. Dr. Melani reported having no relevant conflicts of interest.

SOURCE: Olszewski AJ et al. ASH 2020, Abstract 705.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

An investigational chimeric antigen receptor T-cell (CAR T-cell) construct targeting two antigens on multiple myeloma cells showed promise in a first-in-humans trial, investigators said.

Among 16 patients with relapsed/refractory, heavily pretreated multiple myeloma who received the dual-targeting construct GC012F, the overall response rate was 93.8%, and all of six patients who received the cells at the highest of three dose levels had stringent complete responses (sCR) and were negative for minimal residual disease (MRD) at 6 months follow-up, reported Weijun Fu, MD, PhD, from Shanghai (China) Changzheng Hospital in an oral abstract presented during the virtual American Society of Hematology annual meeting.

GC012F is a novel CAR-T cell platform targeting both the B-cell maturation antigen (BCMA), which is universally expressed on malignant plasma cells, and CD19, which is expressed on both multiple myeloma cells and progenitors, Dr. Fu said.

“Targeting CD19 can trigger elimination of malignant cells by CAR T. Our preclinical work demonstrated more effective elimination of multiple myeloma clone-forming cells by BCMA and CD19 dual CAR T, so targeting both BCMA and CD19 antigens could improve efficacy and reduce relapse,” he said.

The construct is created using the FasTCAR platform that, according to manufacturer Gracell Biotechnologies (Shanghai), allows for cell culturing and expansion within 24-36 hours, rather than 2-3 weeks required for other CAR T-cell products.
 

Investigator-initiated trial

In a phase 1 investigator-initiated trial, 16 patients with a median age of 56 (range 27-71) years were enrolled. The patients all had relapsed or refractory multiple myeloma according to 2016 International Myeloma Working Group criteria, with a life expectancy of at least 3 months and adequate organ function.

The median time since diagnosis was 3 years (range 1-10). All but one of the 16 patients had high-risk disease, 3 had double-hit disease (the presence of two deletions, gain of function, or p53 mutation), and 5 patients had one or more extramedullary plasmacytomas. Four of the patients had received therapy with an anti-CD38 monoclonal antibody.

Following lymphodepletion with fludarabine and cyclophosphamide, the patients received the CAR T cells in a single infusion at dose levels of either 1, 2, or 3 times 10⁵ cells/kg.

As of the cutoff date in July 2020, 15 of the 16 patients had a clinical response, including 9 with a CR or sCR, and 6 with a very good partial response (VGPR). As noted before, all of the six patients treated at the highest dose level had a sCR. At the median follow-up of 7.3 months, the median duration of response had not been reached.

Among all patients evaluable for response at month 1 (14 patients), 11 were MRD negative by flow cytometry. At month 3 all 11 evaluable patients were MRD negative, and all of 10 patients evaluable at 6 months were also MRD negative.

As with other CAR T-cell constructs, all patients developed the cytokine-release syndrome (CRS), with grade 1 or 2 severity in 14 patients, and grade 3 in 2 patients. The median time to onset of CRS was 6 days (range 2-10), and the median duration was 4 days (range 1-8 days).

No cases of immune effector cell–associated neurotoxicity syndrome (ICANS) were observed.

One patient treated at the middle dose level presented with fever and died shortly after day 78 of an unknown cause during the COVID-19 pandemic. Two patients died of extramedullary disease; each had achieved MRD negativity.

Investigators continue to follow the patients and are enrolling new patients in the ongoing study.
 

‘Interesting approach’

Sandy W. Wong, MD, from the Helen Diller Family Comprehensive Cancer Center at the University of California San Francisco, who was not involved in the study, said in an interview that the dual-targeted approach is interesting, in light of a case report presented at ASH 2020 of a patient with multiple myeloma who had a partial response to CAR T-cell therapy with a different construct and who developed a subsequent biallelic loss of BCMA that resulted in resistance to CAR T-cell therapy.

“This raises the idea that, if we perhaps had a dual-targeted CAR T, perhaps we will prolong progression-free survival, in order to avoid antigen escape. So I do think the concept is very interesting and does deserve further study,” she said.

CD19 is thought to be expressed on myeloma stem cells, “so the question is: Are patients not being cured because there is a reservoir of myeloma cells, and targeting CD19 is thought to get at this putative myeloma stem cell? but that remains to be seen,” she added.

Dr. Wong comoderated the session where Dr. Fu presented the data.

The study was supported by participating medical centers and Gracell Biotechnologies. Dr. Fu and Dr. Wong reported no relevant conflicts of interest to disclose.

SOURCE: Jiang H et al. ASH 2020, Abstract 178.

An investigational chimeric antigen receptor T-cell (CAR T-cell) construct targeting two antigens on multiple myeloma cells showed promise in a first-in-humans trial, investigators said.

Among 16 patients with relapsed/refractory, heavily pretreated multiple myeloma who received the dual-targeting construct GC012F, the overall response rate was 93.8%, and all of six patients who received the cells at the highest of three dose levels had stringent complete responses (sCR) and were negative for minimal residual disease (MRD) at 6 months follow-up, reported Weijun Fu, MD, PhD, from Shanghai (China) Changzheng Hospital in an oral abstract presented during the virtual American Society of Hematology annual meeting.

GC012F is a novel CAR-T cell platform targeting both the B-cell maturation antigen (BCMA), which is universally expressed on malignant plasma cells, and CD19, which is expressed on both multiple myeloma cells and progenitors, Dr. Fu said.

“Targeting CD19 can trigger elimination of malignant cells by CAR T. Our preclinical work demonstrated more effective elimination of multiple myeloma clone-forming cells by BCMA and CD19 dual CAR T, so targeting both BCMA and CD19 antigens could improve efficacy and reduce relapse,” he said.

The construct is created using the FasTCAR platform that, according to manufacturer Gracell Biotechnologies (Shanghai), allows for cell culturing and expansion within 24-36 hours, rather than 2-3 weeks required for other CAR T-cell products.
 

Investigator-initiated trial

In a phase 1 investigator-initiated trial, 16 patients with a median age of 56 (range 27-71) years were enrolled. The patients all had relapsed or refractory multiple myeloma according to 2016 International Myeloma Working Group criteria, with a life expectancy of at least 3 months and adequate organ function.

The median time since diagnosis was 3 years (range 1-10). All but one of the 16 patients had high-risk disease, 3 had double-hit disease (the presence of two deletions, gain of function, or p53 mutation), and 5 patients had one or more extramedullary plasmacytomas. Four of the patients had received therapy with an anti-CD38 monoclonal antibody.

Following lymphodepletion with fludarabine and cyclophosphamide, the patients received the CAR T cells in a single infusion at dose levels of either 1, 2, or 3 times 10⁵ cells/kg.

As of the cutoff date in July 2020, 15 of the 16 patients had a clinical response, including 9 with a CR or sCR, and 6 with a very good partial response (VGPR). As noted before, all of the six patients treated at the highest dose level had a sCR. At the median follow-up of 7.3 months, the median duration of response had not been reached.

Among all patients evaluable for response at month 1 (14 patients), 11 were MRD negative by flow cytometry. At month 3 all 11 evaluable patients were MRD negative, and all of 10 patients evaluable at 6 months were also MRD negative.

As with other CAR T-cell constructs, all patients developed the cytokine-release syndrome (CRS), with grade 1 or 2 severity in 14 patients, and grade 3 in 2 patients. The median time to onset of CRS was 6 days (range 2-10), and the median duration was 4 days (range 1-8 days).

No cases of immune effector cell–associated neurotoxicity syndrome (ICANS) were observed.

One patient treated at the middle dose level presented with fever and died shortly after day 78 of an unknown cause during the COVID-19 pandemic. Two patients died of extramedullary disease; each had achieved MRD negativity.

Investigators continue to follow the patients and are enrolling new patients in the ongoing study.
 

‘Interesting approach’

Sandy W. Wong, MD, from the Helen Diller Family Comprehensive Cancer Center at the University of California San Francisco, who was not involved in the study, said in an interview that the dual-targeted approach is interesting, in light of a case report presented at ASH 2020 of a patient with multiple myeloma who had a partial response to CAR T-cell therapy with a different construct and who developed a subsequent biallelic loss of BCMA that resulted in resistance to CAR T-cell therapy.

“This raises the idea that, if we perhaps had a dual-targeted CAR T, perhaps we will prolong progression-free survival, in order to avoid antigen escape. So I do think the concept is very interesting and does deserve further study,” she said.

CD19 is thought to be expressed on myeloma stem cells, “so the question is: Are patients not being cured because there is a reservoir of myeloma cells, and targeting CD19 is thought to get at this putative myeloma stem cell? but that remains to be seen,” she added.

Dr. Wong comoderated the session where Dr. Fu presented the data.

The study was supported by participating medical centers and Gracell Biotechnologies. Dr. Fu and Dr. Wong reported no relevant conflicts of interest to disclose.

SOURCE: Jiang H et al. ASH 2020, Abstract 178.

An investigational chimeric antigen receptor T-cell (CAR T-cell) construct targeting two antigens on multiple myeloma cells showed promise in a first-in-humans trial, investigators said.

Among 16 patients with relapsed/refractory, heavily pretreated multiple myeloma who received the dual-targeting construct GC012F, the overall response rate was 93.8%, and all of six patients who received the cells at the highest of three dose levels had stringent complete responses (sCR) and were negative for minimal residual disease (MRD) at 6 months follow-up, reported Weijun Fu, MD, PhD, from Shanghai (China) Changzheng Hospital in an oral abstract presented during the virtual American Society of Hematology annual meeting.

GC012F is a novel CAR-T cell platform targeting both the B-cell maturation antigen (BCMA), which is universally expressed on malignant plasma cells, and CD19, which is expressed on both multiple myeloma cells and progenitors, Dr. Fu said.

“Targeting CD19 can trigger elimination of malignant cells by CAR T. Our preclinical work demonstrated more effective elimination of multiple myeloma clone-forming cells by BCMA and CD19 dual CAR T, so targeting both BCMA and CD19 antigens could improve efficacy and reduce relapse,” he said.

The construct is created using the FasTCAR platform that, according to manufacturer Gracell Biotechnologies (Shanghai), allows for cell culturing and expansion within 24-36 hours, rather than 2-3 weeks required for other CAR T-cell products.
 

Investigator-initiated trial

In a phase 1 investigator-initiated trial, 16 patients with a median age of 56 (range 27-71) years were enrolled. The patients all had relapsed or refractory multiple myeloma according to 2016 International Myeloma Working Group criteria, with a life expectancy of at least 3 months and adequate organ function.

The median time since diagnosis was 3 years (range 1-10). All but one of the 16 patients had high-risk disease, 3 had double-hit disease (the presence of two deletions, gain of function, or p53 mutation), and 5 patients had one or more extramedullary plasmacytomas. Four of the patients had received therapy with an anti-CD38 monoclonal antibody.

Following lymphodepletion with fludarabine and cyclophosphamide, the patients received the CAR T cells in a single infusion at dose levels of either 1, 2, or 3 times 10⁵ cells/kg.

As of the cutoff date in July 2020, 15 of the 16 patients had a clinical response, including 9 with a CR or sCR, and 6 with a very good partial response (VGPR). As noted before, all of the six patients treated at the highest dose level had a sCR. At the median follow-up of 7.3 months, the median duration of response had not been reached.

Among all patients evaluable for response at month 1 (14 patients), 11 were MRD negative by flow cytometry. At month 3 all 11 evaluable patients were MRD negative, and all of 10 patients evaluable at 6 months were also MRD negative.

As with other CAR T-cell constructs, all patients developed the cytokine-release syndrome (CRS), with grade 1 or 2 severity in 14 patients, and grade 3 in 2 patients. The median time to onset of CRS was 6 days (range 2-10), and the median duration was 4 days (range 1-8 days).

No cases of immune effector cell–associated neurotoxicity syndrome (ICANS) were observed.

One patient treated at the middle dose level presented with fever and died shortly after day 78 of an unknown cause during the COVID-19 pandemic. Two patients died of extramedullary disease; each had achieved MRD negativity.

Investigators continue to follow the patients and are enrolling new patients in the ongoing study.
 

‘Interesting approach’

Sandy W. Wong, MD, from the Helen Diller Family Comprehensive Cancer Center at the University of California San Francisco, who was not involved in the study, said in an interview that the dual-targeted approach is interesting, in light of a case report presented at ASH 2020 of a patient with multiple myeloma who had a partial response to CAR T-cell therapy with a different construct and who developed a subsequent biallelic loss of BCMA that resulted in resistance to CAR T-cell therapy.

“This raises the idea that, if we perhaps had a dual-targeted CAR T, perhaps we will prolong progression-free survival, in order to avoid antigen escape. So I do think the concept is very interesting and does deserve further study,” she said.

CD19 is thought to be expressed on myeloma stem cells, “so the question is: Are patients not being cured because there is a reservoir of myeloma cells, and targeting CD19 is thought to get at this putative myeloma stem cell? but that remains to be seen,” she added.

Dr. Wong comoderated the session where Dr. Fu presented the data.

The study was supported by participating medical centers and Gracell Biotechnologies. Dr. Fu and Dr. Wong reported no relevant conflicts of interest to disclose.

SOURCE: Jiang H et al. ASH 2020, Abstract 178.

A phase 1 first-in-human study demonstrated synthetic T-cell receptor and antigen receptor (STAR) technical feasibility, clinical safety and efficacy in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia (ALL), according to senior study author Peihua Lu, MD, Beijing Lu Daopei Institute of Hematology, Beijing, China. STAR T cells were found to be superior to conventional chimeric antigen receptor (CAR) T cells with respect to signaling capacity, cytokine production and antitumor potency in an animal model study, according to Dr. Lu’s presentation at the annual meeting of the American Society of Hematology.
 

Remission can be improved

While CAR T-cell therapy has demonstrated high response rates in patients with B-cell malignancies, remission durability and safety can be improved, Dr Lu said. Her team developed STAR, a novel double-chain chimeric receptor consisting of two protein modules, each containing an antibody light or heavy chain variable region, the T cell receptor (TCR) alpha or beta chain constant region fused to the OX-40 costimulatory domain. The 2 modules are linked by a self-cleaving Furin-p2A sequence that allows the modules to be proteolytically separated and reconstituted. In preclinical in vitro research, STAR-T-cells showed a much faster and stronger cell activation, compared with CAR T cells and superior target cell–killing ability, and higher levels of interferon-y after coculture with the CD19+ Raji cell. In a murine in vivo study, STAR-T cells had higher antileukemia activity, compared with CAR-T cells, and significantly inhibited tumor cell growth, Dr. Lu stated. All animals were sustainably tumor free 5 days after STAR-T cell injection.

The first-in-human study included 18 CD19+ relapsed/refractory B-cell ALL (median age 22.5 years) patients, with a median bone marrow blast level pre–CAR T of 15.3%.

The manufacture success rate was 100% and took about 9 days (7-13). Transduction efficacy was 57.4% (41.0%-78.2%). Subjects received a conditioning regimen of intravenous fludarabine (25mg/m² per day) and cyclophosphamide (250mg/m² per day) for 3 days followed by a single STAR T-cell infusion. Patients were given the option, after they achieved complete remission (CR), of proceeding to consolidation allogeneic hematopoietic stem cell transplantation (allo-HSCT).
 

100% MRD negative

On day 14 following transplant, 18/18 had achieved minimal residual disease–negative complete response/CRi (with incomplete hematologic recovery). One patient relapsed after allogeneic transplant, becoming minimal residual disease positive on day 28. After a median follow-up of 105 days, 11/18 bridged into allo-HSCT without relapse. Among the seven patients who did not undergo allo-HSCT, one relapsed on day 58 and died on day 63. The patient had CNS leukemia and 87% bone marrow blasts before receiving STAR T. The others, Dr. Lu said, remain in CR.

Mild cytokine release syndrome (CRS) occurred in only 10 patients (55.6%), with grade 1 CRS in 8 patients and grade 2 in 2 patients. Grade 3 neurotoxicity occurred in two patients.

Reporting cellular kinetics of STAR T cells in peripheral blood by fluorescence-activated cell sorting (FACS)/quantitative PCR showed the highest STAR-T proliferation ratio (STAR/CD3) of 88.1%. Median peak level was 4.9 x 10⁴ copies number/mcg genomic DNA. The peak time was day 8.5 and the longest detection time was 6 months after STAR T infusion (STAR T ratio, 0.46%-1.85%). High in vivo proliferation and persistence was observed regardless of infusion dose.
 

STAR holds promise

Dr. Lu concluded: “The phase 1 first-in-human study demonstrated technical feasibility, clinical safety and efficacy of STAR T in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia.” She noted also that long-term observation of these patients and studies of larger patient cohorts are warranted to evaluate a beneficial advantage of the STAR T over the conventional CAR T product.

Asked about future directions in the discussion period, Dr. Lu responded that “this product holds great promise, No. 1 because it is actually between a T-cell receptor and a CAR T, and so clearly has fewer side effects. It potentially can recognize and target the tumor intracellular antigen better than a conventional CAR T. It is easier to construct – and holds great promise for treating solid tumors.”

Dr. Lu reported that she had no relevant disclosures.

SOURCE: Lu P et al. ASH 2020, Abstract 270.

A phase 1 first-in-human study demonstrated synthetic T-cell receptor and antigen receptor (STAR) technical feasibility, clinical safety and efficacy in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia (ALL), according to senior study author Peihua Lu, MD, Beijing Lu Daopei Institute of Hematology, Beijing, China. STAR T cells were found to be superior to conventional chimeric antigen receptor (CAR) T cells with respect to signaling capacity, cytokine production and antitumor potency in an animal model study, according to Dr. Lu’s presentation at the annual meeting of the American Society of Hematology.
 

Remission can be improved

While CAR T-cell therapy has demonstrated high response rates in patients with B-cell malignancies, remission durability and safety can be improved, Dr Lu said. Her team developed STAR, a novel double-chain chimeric receptor consisting of two protein modules, each containing an antibody light or heavy chain variable region, the T cell receptor (TCR) alpha or beta chain constant region fused to the OX-40 costimulatory domain. The 2 modules are linked by a self-cleaving Furin-p2A sequence that allows the modules to be proteolytically separated and reconstituted. In preclinical in vitro research, STAR-T-cells showed a much faster and stronger cell activation, compared with CAR T cells and superior target cell–killing ability, and higher levels of interferon-y after coculture with the CD19+ Raji cell. In a murine in vivo study, STAR-T cells had higher antileukemia activity, compared with CAR-T cells, and significantly inhibited tumor cell growth, Dr. Lu stated. All animals were sustainably tumor free 5 days after STAR-T cell injection.

The first-in-human study included 18 CD19+ relapsed/refractory B-cell ALL (median age 22.5 years) patients, with a median bone marrow blast level pre–CAR T of 15.3%.

The manufacture success rate was 100% and took about 9 days (7-13). Transduction efficacy was 57.4% (41.0%-78.2%). Subjects received a conditioning regimen of intravenous fludarabine (25mg/m² per day) and cyclophosphamide (250mg/m² per day) for 3 days followed by a single STAR T-cell infusion. Patients were given the option, after they achieved complete remission (CR), of proceeding to consolidation allogeneic hematopoietic stem cell transplantation (allo-HSCT).
 

100% MRD negative

On day 14 following transplant, 18/18 had achieved minimal residual disease–negative complete response/CRi (with incomplete hematologic recovery). One patient relapsed after allogeneic transplant, becoming minimal residual disease positive on day 28. After a median follow-up of 105 days, 11/18 bridged into allo-HSCT without relapse. Among the seven patients who did not undergo allo-HSCT, one relapsed on day 58 and died on day 63. The patient had CNS leukemia and 87% bone marrow blasts before receiving STAR T. The others, Dr. Lu said, remain in CR.

Mild cytokine release syndrome (CRS) occurred in only 10 patients (55.6%), with grade 1 CRS in 8 patients and grade 2 in 2 patients. Grade 3 neurotoxicity occurred in two patients.

Reporting cellular kinetics of STAR T cells in peripheral blood by fluorescence-activated cell sorting (FACS)/quantitative PCR showed the highest STAR-T proliferation ratio (STAR/CD3) of 88.1%. Median peak level was 4.9 x 10⁴ copies number/mcg genomic DNA. The peak time was day 8.5 and the longest detection time was 6 months after STAR T infusion (STAR T ratio, 0.46%-1.85%). High in vivo proliferation and persistence was observed regardless of infusion dose.
 

STAR holds promise

Dr. Lu concluded: “The phase 1 first-in-human study demonstrated technical feasibility, clinical safety and efficacy of STAR T in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia.” She noted also that long-term observation of these patients and studies of larger patient cohorts are warranted to evaluate a beneficial advantage of the STAR T over the conventional CAR T product.

Asked about future directions in the discussion period, Dr. Lu responded that “this product holds great promise, No. 1 because it is actually between a T-cell receptor and a CAR T, and so clearly has fewer side effects. It potentially can recognize and target the tumor intracellular antigen better than a conventional CAR T. It is easier to construct – and holds great promise for treating solid tumors.”

Dr. Lu reported that she had no relevant disclosures.

SOURCE: Lu P et al. ASH 2020, Abstract 270.

A phase 1 first-in-human study demonstrated synthetic T-cell receptor and antigen receptor (STAR) technical feasibility, clinical safety and efficacy in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia (ALL), according to senior study author Peihua Lu, MD, Beijing Lu Daopei Institute of Hematology, Beijing, China. STAR T cells were found to be superior to conventional chimeric antigen receptor (CAR) T cells with respect to signaling capacity, cytokine production and antitumor potency in an animal model study, according to Dr. Lu’s presentation at the annual meeting of the American Society of Hematology.
 

Remission can be improved

While CAR T-cell therapy has demonstrated high response rates in patients with B-cell malignancies, remission durability and safety can be improved, Dr Lu said. Her team developed STAR, a novel double-chain chimeric receptor consisting of two protein modules, each containing an antibody light or heavy chain variable region, the T cell receptor (TCR) alpha or beta chain constant region fused to the OX-40 costimulatory domain. The 2 modules are linked by a self-cleaving Furin-p2A sequence that allows the modules to be proteolytically separated and reconstituted. In preclinical in vitro research, STAR-T-cells showed a much faster and stronger cell activation, compared with CAR T cells and superior target cell–killing ability, and higher levels of interferon-y after coculture with the CD19+ Raji cell. In a murine in vivo study, STAR-T cells had higher antileukemia activity, compared with CAR-T cells, and significantly inhibited tumor cell growth, Dr. Lu stated. All animals were sustainably tumor free 5 days after STAR-T cell injection.

The first-in-human study included 18 CD19+ relapsed/refractory B-cell ALL (median age 22.5 years) patients, with a median bone marrow blast level pre–CAR T of 15.3%.

The manufacture success rate was 100% and took about 9 days (7-13). Transduction efficacy was 57.4% (41.0%-78.2%). Subjects received a conditioning regimen of intravenous fludarabine (25mg/m² per day) and cyclophosphamide (250mg/m² per day) for 3 days followed by a single STAR T-cell infusion. Patients were given the option, after they achieved complete remission (CR), of proceeding to consolidation allogeneic hematopoietic stem cell transplantation (allo-HSCT).
 

100% MRD negative

On day 14 following transplant, 18/18 had achieved minimal residual disease–negative complete response/CRi (with incomplete hematologic recovery). One patient relapsed after allogeneic transplant, becoming minimal residual disease positive on day 28. After a median follow-up of 105 days, 11/18 bridged into allo-HSCT without relapse. Among the seven patients who did not undergo allo-HSCT, one relapsed on day 58 and died on day 63. The patient had CNS leukemia and 87% bone marrow blasts before receiving STAR T. The others, Dr. Lu said, remain in CR.

Mild cytokine release syndrome (CRS) occurred in only 10 patients (55.6%), with grade 1 CRS in 8 patients and grade 2 in 2 patients. Grade 3 neurotoxicity occurred in two patients.

Reporting cellular kinetics of STAR T cells in peripheral blood by fluorescence-activated cell sorting (FACS)/quantitative PCR showed the highest STAR-T proliferation ratio (STAR/CD3) of 88.1%. Median peak level was 4.9 x 10⁴ copies number/mcg genomic DNA. The peak time was day 8.5 and the longest detection time was 6 months after STAR T infusion (STAR T ratio, 0.46%-1.85%). High in vivo proliferation and persistence was observed regardless of infusion dose.
 

STAR holds promise

Dr. Lu concluded: “The phase 1 first-in-human study demonstrated technical feasibility, clinical safety and efficacy of STAR T in treating CD19+ relapsed/refractory B-cell acute lymphoblastic leukemia.” She noted also that long-term observation of these patients and studies of larger patient cohorts are warranted to evaluate a beneficial advantage of the STAR T over the conventional CAR T product.

Asked about future directions in the discussion period, Dr. Lu responded that “this product holds great promise, No. 1 because it is actually between a T-cell receptor and a CAR T, and so clearly has fewer side effects. It potentially can recognize and target the tumor intracellular antigen better than a conventional CAR T. It is easier to construct – and holds great promise for treating solid tumors.”

Dr. Lu reported that she had no relevant disclosures.

SOURCE: Lu P et al. ASH 2020, Abstract 270.

For B-cell malignancies, synthetic lethality is a viable treatment approach, according to preliminary clinical trial data with once-daily oral DTRM-555. The triple combination therapy, DTRM-555, combines a Bruton’s tyrosine kinase (BTK) inhibitor, a mammalian target of rapamycin (mTOR) inhibitor and pomalidomide, an immunomodulatory imide drug (IMiD), according to Anthony R. Mato, MD, in a presentation at the annual meeting of the American Society of Hematology, which was held virtually.
 

Richter’s transformation, a rare event

Dr. Mato’s phase 1 clinical trial included 13 patients with Richter’s transformation (RT) and 11 with diffuse large B-cell lymphoma (DLBCL). Richter’s transformation, a rare event occurring in 5%-7% of chronic lymphocytic leukemia (CLL) cases, has no clear standard of care and universally poor outcomes (overall survival, 3-12 months) once it becomes refractory to anthracycline-based chemotherapy, according to Dr. Mato.

Despite great progress in treating DLBCL, cure rates with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone), the standard of care, are in the 50%-60% range and much lower (30%-40%) with poor-risk features. Furthermore, most (60%-70%) patients receiving autologous stem cell transplant or CAR-T still require additional lines of therapy.

The “synthetic lethality” (SL) strategy, which has become a focus of cancer treatment in the last decade, identifies multiple disease primary aberrant and compensatory pathways and then inhibits them together in a manner lethal to cell survival. Preclinical studies have shown low doses of a BTK inhibitor/mTOR inhibitor/IMiD to synergistically kill malignant B cells. DTRM-555 is an optimized, oral, once-daily triplet combination of a novel and clinically differentiated irreversible BTK inhibitor (DTRM-12), everolimus and pomalidomide, Dr. Mato explained.

Individuals (38% women) included in the trial had a median of 2 (1-10) prior lines of therapy, with a CD20 monoclonal antibody as one of them in all cases, and 83% with R-CHOP. All patients had life expectancy >12 weeks, with 0-1 performance status and adequate organ and hematologic function.

DTRM-12 plasma concentrations, Dr. Mato noted, were unaffected by coadministration with everolimus with or without pomalidomide.
 

Manageable adverse events

Among adverse events, neutropenia (grade 3-4, 33%/21%) and thrombocytopenia (grade 3-4, 29%/8%) were most common. One patient had grade 4 leukopenia (4%). No patients discontinued treatment on account of adverse events, however, and nonhematologic adverse event rates were low, without grade 4 events. Eight different grade 3 adverse events (atrial fibrillation [with prior history], diarrhea, hyponatremia pneumonia, pulmonary opportunistic infection, rash maculopapular, rash acneiform, skin ulceration) were reported, each in one patient. Pharmacokinetic data supported once-daily dosing for DTRM-12, with an estimated half-life of 5-9 hours that was comparable with that of once-daily ibrutinib, and longer than that of other agents of the same class. The recommended phase 2 dose going forward was 200 mg for DTRM-12, 5 mg for everolimus and 2 mg for pomalidomide.
 

Favorable responses

In efficacy analysis for 22 evaluable patients (11 in the RT group, 11 in the DLBCL ), there was 1 complete response in the RT group and 2 in the DLBCL group, with partial responses in 4 and 3, respectively, giving overall response rates of 46% in the RT group and 45% in the DLBCL group. Two and four patients, respectively, in the RT and DLBCL groups, had stable disease, Dr. Mato said, and most patients (71%) had SPD (sum of the product of the diameters) lymph node reductions, with lymph node reductions of 50% or more in 43%.

“Encouraging clinical activity was observed in high-risk, heavily pretreated Richter’s transformation and diffuse large B-cell lymphoma patients,” Dr. Mato concluded. He also noted that the main safety findings were “expected and manageable.”

The session moderator, Chaitra S. Ujjani, MD, of the Seattle Health Care Alliance, asked if the DTRM-555 regimen should be considered definitive therapy in patients who are responding, or if moving on to cellular therapies or a consolidative approach should be considered.

“If they are responding, it is reasonable to consider consolidating with a cellular therapy at this point in time,” Dr. Mato replied. He did observe, however, that many of the included patients had tried experimental therapies, including cellular therapy. “Without [data from] a much larger patient population and longer-term follow-up, I think that, for responding patients with a durable remission who have a [chimeric antigen receptor] T or transplant option, these, at the least, have to be discussed with them.”

To an additional question as to whether any of the subjects had prior exposure to BTK inhibitors, Dr. Mato responded, “There is a high exposure to BTK inhibitors, and almost universally these patients were progressors. So again, this is supportive of the hypothesis that hitting multiple pathways simultaneously is somewhat different from hitting just BTK by itself, even in the setting of progression.”

A DTRM-555 triple fixed-dose combination tablet is under development, and a double fixed-dose tablet (DTRM-505) is ready for the ongoing phase 2 U.S. study (NCT04030544) among patients with relapsed/refractory CLL or non-Hodgkin lymphoma (RT, DLBCL or transformed follicular lymphoma) with prior exposure to a novel agent.

Dr. Mato, disclosed consultancy and research funding relationships with multiple pharmaceutical and biotechnology companies.

SOURCE: Mato AR et al. ASH 2020, Abstract 126.

For B-cell malignancies, synthetic lethality is a viable treatment approach, according to preliminary clinical trial data with once-daily oral DTRM-555. The triple combination therapy, DTRM-555, combines a Bruton’s tyrosine kinase (BTK) inhibitor, a mammalian target of rapamycin (mTOR) inhibitor and pomalidomide, an immunomodulatory imide drug (IMiD), according to Anthony R. Mato, MD, in a presentation at the annual meeting of the American Society of Hematology, which was held virtually.
 

Richter’s transformation, a rare event

Dr. Mato’s phase 1 clinical trial included 13 patients with Richter’s transformation (RT) and 11 with diffuse large B-cell lymphoma (DLBCL). Richter’s transformation, a rare event occurring in 5%-7% of chronic lymphocytic leukemia (CLL) cases, has no clear standard of care and universally poor outcomes (overall survival, 3-12 months) once it becomes refractory to anthracycline-based chemotherapy, according to Dr. Mato.

Despite great progress in treating DLBCL, cure rates with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone), the standard of care, are in the 50%-60% range and much lower (30%-40%) with poor-risk features. Furthermore, most (60%-70%) patients receiving autologous stem cell transplant or CAR-T still require additional lines of therapy.

The “synthetic lethality” (SL) strategy, which has become a focus of cancer treatment in the last decade, identifies multiple disease primary aberrant and compensatory pathways and then inhibits them together in a manner lethal to cell survival. Preclinical studies have shown low doses of a BTK inhibitor/mTOR inhibitor/IMiD to synergistically kill malignant B cells. DTRM-555 is an optimized, oral, once-daily triplet combination of a novel and clinically differentiated irreversible BTK inhibitor (DTRM-12), everolimus and pomalidomide, Dr. Mato explained.

Individuals (38% women) included in the trial had a median of 2 (1-10) prior lines of therapy, with a CD20 monoclonal antibody as one of them in all cases, and 83% with R-CHOP. All patients had life expectancy >12 weeks, with 0-1 performance status and adequate organ and hematologic function.

DTRM-12 plasma concentrations, Dr. Mato noted, were unaffected by coadministration with everolimus with or without pomalidomide.
 

Manageable adverse events

Among adverse events, neutropenia (grade 3-4, 33%/21%) and thrombocytopenia (grade 3-4, 29%/8%) were most common. One patient had grade 4 leukopenia (4%). No patients discontinued treatment on account of adverse events, however, and nonhematologic adverse event rates were low, without grade 4 events. Eight different grade 3 adverse events (atrial fibrillation [with prior history], diarrhea, hyponatremia pneumonia, pulmonary opportunistic infection, rash maculopapular, rash acneiform, skin ulceration) were reported, each in one patient. Pharmacokinetic data supported once-daily dosing for DTRM-12, with an estimated half-life of 5-9 hours that was comparable with that of once-daily ibrutinib, and longer than that of other agents of the same class. The recommended phase 2 dose going forward was 200 mg for DTRM-12, 5 mg for everolimus and 2 mg for pomalidomide.
 

Favorable responses

In efficacy analysis for 22 evaluable patients (11 in the RT group, 11 in the DLBCL ), there was 1 complete response in the RT group and 2 in the DLBCL group, with partial responses in 4 and 3, respectively, giving overall response rates of 46% in the RT group and 45% in the DLBCL group. Two and four patients, respectively, in the RT and DLBCL groups, had stable disease, Dr. Mato said, and most patients (71%) had SPD (sum of the product of the diameters) lymph node reductions, with lymph node reductions of 50% or more in 43%.

“Encouraging clinical activity was observed in high-risk, heavily pretreated Richter’s transformation and diffuse large B-cell lymphoma patients,” Dr. Mato concluded. He also noted that the main safety findings were “expected and manageable.”

The session moderator, Chaitra S. Ujjani, MD, of the Seattle Health Care Alliance, asked if the DTRM-555 regimen should be considered definitive therapy in patients who are responding, or if moving on to cellular therapies or a consolidative approach should be considered.

“If they are responding, it is reasonable to consider consolidating with a cellular therapy at this point in time,” Dr. Mato replied. He did observe, however, that many of the included patients had tried experimental therapies, including cellular therapy. “Without [data from] a much larger patient population and longer-term follow-up, I think that, for responding patients with a durable remission who have a [chimeric antigen receptor] T or transplant option, these, at the least, have to be discussed with them.”

To an additional question as to whether any of the subjects had prior exposure to BTK inhibitors, Dr. Mato responded, “There is a high exposure to BTK inhibitors, and almost universally these patients were progressors. So again, this is supportive of the hypothesis that hitting multiple pathways simultaneously is somewhat different from hitting just BTK by itself, even in the setting of progression.”

A DTRM-555 triple fixed-dose combination tablet is under development, and a double fixed-dose tablet (DTRM-505) is ready for the ongoing phase 2 U.S. study (NCT04030544) among patients with relapsed/refractory CLL or non-Hodgkin lymphoma (RT, DLBCL or transformed follicular lymphoma) with prior exposure to a novel agent.

Dr. Mato, disclosed consultancy and research funding relationships with multiple pharmaceutical and biotechnology companies.

SOURCE: Mato AR et al. ASH 2020, Abstract 126.

For B-cell malignancies, synthetic lethality is a viable treatment approach, according to preliminary clinical trial data with once-daily oral DTRM-555. The triple combination therapy, DTRM-555, combines a Bruton’s tyrosine kinase (BTK) inhibitor, a mammalian target of rapamycin (mTOR) inhibitor and pomalidomide, an immunomodulatory imide drug (IMiD), according to Anthony R. Mato, MD, in a presentation at the annual meeting of the American Society of Hematology, which was held virtually.
 

Richter’s transformation, a rare event

Dr. Mato’s phase 1 clinical trial included 13 patients with Richter’s transformation (RT) and 11 with diffuse large B-cell lymphoma (DLBCL). Richter’s transformation, a rare event occurring in 5%-7% of chronic lymphocytic leukemia (CLL) cases, has no clear standard of care and universally poor outcomes (overall survival, 3-12 months) once it becomes refractory to anthracycline-based chemotherapy, according to Dr. Mato.

Despite great progress in treating DLBCL, cure rates with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone), the standard of care, are in the 50%-60% range and much lower (30%-40%) with poor-risk features. Furthermore, most (60%-70%) patients receiving autologous stem cell transplant or CAR-T still require additional lines of therapy.

The “synthetic lethality” (SL) strategy, which has become a focus of cancer treatment in the last decade, identifies multiple disease primary aberrant and compensatory pathways and then inhibits them together in a manner lethal to cell survival. Preclinical studies have shown low doses of a BTK inhibitor/mTOR inhibitor/IMiD to synergistically kill malignant B cells. DTRM-555 is an optimized, oral, once-daily triplet combination of a novel and clinically differentiated irreversible BTK inhibitor (DTRM-12), everolimus and pomalidomide, Dr. Mato explained.

Individuals (38% women) included in the trial had a median of 2 (1-10) prior lines of therapy, with a CD20 monoclonal antibody as one of them in all cases, and 83% with R-CHOP. All patients had life expectancy >12 weeks, with 0-1 performance status and adequate organ and hematologic function.

DTRM-12 plasma concentrations, Dr. Mato noted, were unaffected by coadministration with everolimus with or without pomalidomide.
 

Manageable adverse events

Among adverse events, neutropenia (grade 3-4, 33%/21%) and thrombocytopenia (grade 3-4, 29%/8%) were most common. One patient had grade 4 leukopenia (4%). No patients discontinued treatment on account of adverse events, however, and nonhematologic adverse event rates were low, without grade 4 events. Eight different grade 3 adverse events (atrial fibrillation [with prior history], diarrhea, hyponatremia pneumonia, pulmonary opportunistic infection, rash maculopapular, rash acneiform, skin ulceration) were reported, each in one patient. Pharmacokinetic data supported once-daily dosing for DTRM-12, with an estimated half-life of 5-9 hours that was comparable with that of once-daily ibrutinib, and longer than that of other agents of the same class. The recommended phase 2 dose going forward was 200 mg for DTRM-12, 5 mg for everolimus and 2 mg for pomalidomide.
 

Favorable responses

In efficacy analysis for 22 evaluable patients (11 in the RT group, 11 in the DLBCL ), there was 1 complete response in the RT group and 2 in the DLBCL group, with partial responses in 4 and 3, respectively, giving overall response rates of 46% in the RT group and 45% in the DLBCL group. Two and four patients, respectively, in the RT and DLBCL groups, had stable disease, Dr. Mato said, and most patients (71%) had SPD (sum of the product of the diameters) lymph node reductions, with lymph node reductions of 50% or more in 43%.

“Encouraging clinical activity was observed in high-risk, heavily pretreated Richter’s transformation and diffuse large B-cell lymphoma patients,” Dr. Mato concluded. He also noted that the main safety findings were “expected and manageable.”

The session moderator, Chaitra S. Ujjani, MD, of the Seattle Health Care Alliance, asked if the DTRM-555 regimen should be considered definitive therapy in patients who are responding, or if moving on to cellular therapies or a consolidative approach should be considered.

“If they are responding, it is reasonable to consider consolidating with a cellular therapy at this point in time,” Dr. Mato replied. He did observe, however, that many of the included patients had tried experimental therapies, including cellular therapy. “Without [data from] a much larger patient population and longer-term follow-up, I think that, for responding patients with a durable remission who have a [chimeric antigen receptor] T or transplant option, these, at the least, have to be discussed with them.”

To an additional question as to whether any of the subjects had prior exposure to BTK inhibitors, Dr. Mato responded, “There is a high exposure to BTK inhibitors, and almost universally these patients were progressors. So again, this is supportive of the hypothesis that hitting multiple pathways simultaneously is somewhat different from hitting just BTK by itself, even in the setting of progression.”

A DTRM-555 triple fixed-dose combination tablet is under development, and a double fixed-dose tablet (DTRM-505) is ready for the ongoing phase 2 U.S. study (NCT04030544) among patients with relapsed/refractory CLL or non-Hodgkin lymphoma (RT, DLBCL or transformed follicular lymphoma) with prior exposure to a novel agent.

Dr. Mato, disclosed consultancy and research funding relationships with multiple pharmaceutical and biotechnology companies.

SOURCE: Mato AR et al. ASH 2020, Abstract 126.

Axicabtagene ciloleucel (axi-cel) can be safely administered and has substantial clinical benefit as part of first-line therapy in patients with high-risk large B-cell lymphoma, according to an investigator in a phase 2 study.

The chimeric antigen receptor (CAR) T-cell therapy had a “very high” overall response rate (ORR) of 85% and a complete response (CR) rate of 74% in the ZUMA-12 study, said investigator Sattva S. Neelapu, MD, of The University of Texas MD Anderson Cancer Center in Houston.

Nearly three-quarters of responses were ongoing with a median of follow-up of about 9 months, Dr. Neelapu said in interim analysis of ZUMA-12 presented at the annual meeting of the American Society of Hematology, which was held virtually.

While axi-cel is approved for treatment of certain relapsed/refractory large B-cell lymphomas (LBCLs), Dr. Neelapu said this is the first-ever study evaluating a CAR T-cell therapy as a first-line treatment for patients with LBCL that is high risk as defined by histology or International Prognostic Index (IPI) scoring.

Treatment with axi-cel was guided by dynamic risk assessment, Dr. Neelapu explained, meaning that patients received the CAR T-cell treatment if they had a positive interim positron emission tomography (PET) scan after two cycles of an anti-CD20 monoclonal antibody and anthracycline-containing regimen.
 

Longer follow-up needed

The interim efficacy analysis is based on 27 evaluable patients out of 40 patients planned to be enrolled, meaning that the final analysis is needed, and longer follow-up is needed to ensure that durability is maintained, Dr. Neelapu said in a question-and-answer session following his presentation.

Nevertheless, the 74% complete response rate in the frontline setting is “quite encouraging” compared to historical data in high-risk LBCL, where CR rates have generally been less than 50%, Dr. Neelapu added.

“Assuming that long-term data in the final analysis confirms this encouraging activity, I think we likely would need a randomized phase 3 trial to compare (axi-cel) head-to-head with frontline therapy,” he said.

Without mature data available, it’s hard to say in this single-arm study how much axi-cel is improving outcomes at the cost of significant toxicity, said Catherine M. Diefenbach, MD, director of the clinical lymphoma program at NYU Langone’s Perlmutter Cancer Center in New York.

Adverse events as reported by Dr. Neelapu included grade 3 cytokine release syndrome (CRS) in 9% of patients, and 25% grade 3 or greater neurologic events in 25%.

“It appears as though it may be salvaging some patients, as the response rate is higher than that expected for chemotherapy alone in this setting,” Dr. Diefenbach said in an interview, “but toxicity is not trivial, so the long-term data will provide better clarity as to the degree of benefit.”
 

Ongoing responses at 9 months

The phase 2 ZUMA-12 study includes patients classified as high risk based on MYC and BCL2 and/or BCL6 translocations, or by an International Prognostic Indicator score of 3 or greater.

Patients initially received two cycles of anti-CD20 monoclonal antibody therapy plus an anthracycline containing regimen. Those with a positive interim PET (score of 4 or 5 on the 5-point Deauville scale) received fludarabine/cyclophosphamide conditioning plus axi-cel as a single intravenous infusion of 2 x 106 CAR T cells per kg of body weight.

As of the report at the ASH meeting, 32 patient had received axi-cel, of whom 32 were evaluable for safety and 27 were evaluable for efficacy.

The ORR was 85% (23 of 27 patients), and the CR rate was 74% (20 of 27 patients), Dr. Neelapu reported, noting that with a median follow-up of 9.3 months, 70% of responders (19 of 27) were in ongoing response.

Median duration of response, progression-free survival, and overall survival have not been reached, he added.

Encephalopathy was the most common grade 3 or greater adverse event related to axi-cel, occurring in 16% of patients, while increased alanine aminotransferase and decreased neutrophil count were each seen in 9% of patients, Dr. Neelapu said.

All 32 patients experienced CRS, including grade 3 CRS in 3 patients (9%), according to the reported data. Neurologic events were seen in 22 patients (69%) including grade 3 or greater in 8 (25%). There were 2 grade 4 neurologic events – both encephalopathies that resolved, according to Dr. Neelapu – and no grade 5 neurologic events.

ZUMA-12 is sponsored by Kite, a Gilead Company. Dr. Neelapu reported disclosures related to Acerta, Adicet Bio, Bristol-Myers Squibb, Kite, and various other pharmaceutical and biotechnology companies.
 

SOURCE: Neelapu SS et al. ASH 2020, Abstract 405.

Axicabtagene ciloleucel (axi-cel) can be safely administered and has substantial clinical benefit as part of first-line therapy in patients with high-risk large B-cell lymphoma, according to an investigator in a phase 2 study.

The chimeric antigen receptor (CAR) T-cell therapy had a “very high” overall response rate (ORR) of 85% and a complete response (CR) rate of 74% in the ZUMA-12 study, said investigator Sattva S. Neelapu, MD, of The University of Texas MD Anderson Cancer Center in Houston.

Nearly three-quarters of responses were ongoing with a median of follow-up of about 9 months, Dr. Neelapu said in interim analysis of ZUMA-12 presented at the annual meeting of the American Society of Hematology, which was held virtually.

While axi-cel is approved for treatment of certain relapsed/refractory large B-cell lymphomas (LBCLs), Dr. Neelapu said this is the first-ever study evaluating a CAR T-cell therapy as a first-line treatment for patients with LBCL that is high risk as defined by histology or International Prognostic Index (IPI) scoring.

Treatment with axi-cel was guided by dynamic risk assessment, Dr. Neelapu explained, meaning that patients received the CAR T-cell treatment if they had a positive interim positron emission tomography (PET) scan after two cycles of an anti-CD20 monoclonal antibody and anthracycline-containing regimen.
 

Longer follow-up needed

The interim efficacy analysis is based on 27 evaluable patients out of 40 patients planned to be enrolled, meaning that the final analysis is needed, and longer follow-up is needed to ensure that durability is maintained, Dr. Neelapu said in a question-and-answer session following his presentation.

Nevertheless, the 74% complete response rate in the frontline setting is “quite encouraging” compared to historical data in high-risk LBCL, where CR rates have generally been less than 50%, Dr. Neelapu added.

“Assuming that long-term data in the final analysis confirms this encouraging activity, I think we likely would need a randomized phase 3 trial to compare (axi-cel) head-to-head with frontline therapy,” he said.

Without mature data available, it’s hard to say in this single-arm study how much axi-cel is improving outcomes at the cost of significant toxicity, said Catherine M. Diefenbach, MD, director of the clinical lymphoma program at NYU Langone’s Perlmutter Cancer Center in New York.

Adverse events as reported by Dr. Neelapu included grade 3 cytokine release syndrome (CRS) in 9% of patients, and 25% grade 3 or greater neurologic events in 25%.

“It appears as though it may be salvaging some patients, as the response rate is higher than that expected for chemotherapy alone in this setting,” Dr. Diefenbach said in an interview, “but toxicity is not trivial, so the long-term data will provide better clarity as to the degree of benefit.”
 

Ongoing responses at 9 months

The phase 2 ZUMA-12 study includes patients classified as high risk based on MYC and BCL2 and/or BCL6 translocations, or by an International Prognostic Indicator score of 3 or greater.

Patients initially received two cycles of anti-CD20 monoclonal antibody therapy plus an anthracycline containing regimen. Those with a positive interim PET (score of 4 or 5 on the 5-point Deauville scale) received fludarabine/cyclophosphamide conditioning plus axi-cel as a single intravenous infusion of 2 x 106 CAR T cells per kg of body weight.

As of the report at the ASH meeting, 32 patient had received axi-cel, of whom 32 were evaluable for safety and 27 were evaluable for efficacy.

The ORR was 85% (23 of 27 patients), and the CR rate was 74% (20 of 27 patients), Dr. Neelapu reported, noting that with a median follow-up of 9.3 months, 70% of responders (19 of 27) were in ongoing response.

Median duration of response, progression-free survival, and overall survival have not been reached, he added.

Encephalopathy was the most common grade 3 or greater adverse event related to axi-cel, occurring in 16% of patients, while increased alanine aminotransferase and decreased neutrophil count were each seen in 9% of patients, Dr. Neelapu said.

All 32 patients experienced CRS, including grade 3 CRS in 3 patients (9%), according to the reported data. Neurologic events were seen in 22 patients (69%) including grade 3 or greater in 8 (25%). There were 2 grade 4 neurologic events – both encephalopathies that resolved, according to Dr. Neelapu – and no grade 5 neurologic events.

ZUMA-12 is sponsored by Kite, a Gilead Company. Dr. Neelapu reported disclosures related to Acerta, Adicet Bio, Bristol-Myers Squibb, Kite, and various other pharmaceutical and biotechnology companies.
 

SOURCE: Neelapu SS et al. ASH 2020, Abstract 405.

Axicabtagene ciloleucel (axi-cel) can be safely administered and has substantial clinical benefit as part of first-line therapy in patients with high-risk large B-cell lymphoma, according to an investigator in a phase 2 study.

The chimeric antigen receptor (CAR) T-cell therapy had a “very high” overall response rate (ORR) of 85% and a complete response (CR) rate of 74% in the ZUMA-12 study, said investigator Sattva S. Neelapu, MD, of The University of Texas MD Anderson Cancer Center in Houston.

Nearly three-quarters of responses were ongoing with a median of follow-up of about 9 months, Dr. Neelapu said in interim analysis of ZUMA-12 presented at the annual meeting of the American Society of Hematology, which was held virtually.

While axi-cel is approved for treatment of certain relapsed/refractory large B-cell lymphomas (LBCLs), Dr. Neelapu said this is the first-ever study evaluating a CAR T-cell therapy as a first-line treatment for patients with LBCL that is high risk as defined by histology or International Prognostic Index (IPI) scoring.

Treatment with axi-cel was guided by dynamic risk assessment, Dr. Neelapu explained, meaning that patients received the CAR T-cell treatment if they had a positive interim positron emission tomography (PET) scan after two cycles of an anti-CD20 monoclonal antibody and anthracycline-containing regimen.
 

Longer follow-up needed

The interim efficacy analysis is based on 27 evaluable patients out of 40 patients planned to be enrolled, meaning that the final analysis is needed, and longer follow-up is needed to ensure that durability is maintained, Dr. Neelapu said in a question-and-answer session following his presentation.

Nevertheless, the 74% complete response rate in the frontline setting is “quite encouraging” compared to historical data in high-risk LBCL, where CR rates have generally been less than 50%, Dr. Neelapu added.

“Assuming that long-term data in the final analysis confirms this encouraging activity, I think we likely would need a randomized phase 3 trial to compare (axi-cel) head-to-head with frontline therapy,” he said.

Without mature data available, it’s hard to say in this single-arm study how much axi-cel is improving outcomes at the cost of significant toxicity, said Catherine M. Diefenbach, MD, director of the clinical lymphoma program at NYU Langone’s Perlmutter Cancer Center in New York.

Adverse events as reported by Dr. Neelapu included grade 3 cytokine release syndrome (CRS) in 9% of patients, and 25% grade 3 or greater neurologic events in 25%.

“It appears as though it may be salvaging some patients, as the response rate is higher than that expected for chemotherapy alone in this setting,” Dr. Diefenbach said in an interview, “but toxicity is not trivial, so the long-term data will provide better clarity as to the degree of benefit.”
 

Ongoing responses at 9 months

The phase 2 ZUMA-12 study includes patients classified as high risk based on MYC and BCL2 and/or BCL6 translocations, or by an International Prognostic Indicator score of 3 or greater.

Patients initially received two cycles of anti-CD20 monoclonal antibody therapy plus an anthracycline containing regimen. Those with a positive interim PET (score of 4 or 5 on the 5-point Deauville scale) received fludarabine/cyclophosphamide conditioning plus axi-cel as a single intravenous infusion of 2 x 106 CAR T cells per kg of body weight.

As of the report at the ASH meeting, 32 patient had received axi-cel, of whom 32 were evaluable for safety and 27 were evaluable for efficacy.

The ORR was 85% (23 of 27 patients), and the CR rate was 74% (20 of 27 patients), Dr. Neelapu reported, noting that with a median follow-up of 9.3 months, 70% of responders (19 of 27) were in ongoing response.

Median duration of response, progression-free survival, and overall survival have not been reached, he added.

Encephalopathy was the most common grade 3 or greater adverse event related to axi-cel, occurring in 16% of patients, while increased alanine aminotransferase and decreased neutrophil count were each seen in 9% of patients, Dr. Neelapu said.

All 32 patients experienced CRS, including grade 3 CRS in 3 patients (9%), according to the reported data. Neurologic events were seen in 22 patients (69%) including grade 3 or greater in 8 (25%). There were 2 grade 4 neurologic events – both encephalopathies that resolved, according to Dr. Neelapu – and no grade 5 neurologic events.

ZUMA-12 is sponsored by Kite, a Gilead Company. Dr. Neelapu reported disclosures related to Acerta, Adicet Bio, Bristol-Myers Squibb, Kite, and various other pharmaceutical and biotechnology companies.
 

SOURCE: Neelapu SS et al. ASH 2020, Abstract 405.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Adolescents and young adults with aggressive mature B-cell non-Hodgkin lymphomas appear to have better outcomes when they’re treated under pediatric protocols rather than adult regimens, Canadian investigators say.

Results of a study of patients from the ages of 15 to 21 years with either diffuse large B-cell lymphoma (DLBCL) or Burkitt’s lymphoma treated at regional or community cancer centers in the province of Ontario indicated that adolescents and young adult (AYA) patients treated at adult centers had a more than fourfold risk for disease relapse or progression, compared with their counterparts who were treated at pediatric centers, reported Sumit Gupta, MD, PhD, from the Hospital for Sick Children in Toronto and colleagues.

“Our data suggest that pediatric approaches are associated with improved event-free survival and overall survival, primarily due to a decrease in the risk of relapse or progression, while still using lower cumulative doses of chemotherapy,” he said in an oral abstract presented at the American Society of Hematology annual meeting, held virtually.

The findings echo those seen in the treatment of patients with acute lymphoblastic leukemia (ALL). As previously reported, a study from Nordic and Baltic countries showed that young adults with ALL who were treated with a pediatric regimen had a 4-year event-free survival rate of 73%, compared with 42% for historical controls.

Similarly, a prospective U.S. study reported in 2014 showed that AYA with ALL treated with a pediatric regimen had better overall and event-free survival rates, compared with historical controls.

As with ALL, pediatric and adult regimens for treatment of patients with aggressive mature B-cell NHL differ substantially, with pediatric patients receiving more intensive short-term therapy with lower cumulative doses.

In addition, while pediatric regimens for DLBCL and Burkitt’s lymphoma are identical, adult regimens differ substantially between the two histologies, Dr. Gupta pointed out.

Adult regimens for DLBCL most often incorporate CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or CHOP plus rituximab (R-CHOP), whereas Burkitt’s lymphoma in adults is generally treated with more aggressive multidrug regimens, in combination with rituximab.

Rituximab was incorporated into adults’ regimens far earlier than in pediatric regimens, with Food and Drug Administration approval of rituximab in frontline therapy of adults with DLBCL in 2006, “whereas the first pediatric large-scale randomized controlled trial of rituximab in pediatric mature B-cell lymphoma was only published earlier this year,” he noted.
 

Population-based study

To see how treatment patterns for AYA patients with aggressive mature B-cell non-Hodgkin lymphomas differ between pediatric and adult centers, Dr. Gupta and colleagues conducted a population-based study of all AYA in Ontario diagnosed with Burkitt’s or DLBCL from the ages of 15 to 21 years from 1992 through 2012.

AYA from the ages of 15 to 18 years who were treated at pediatric centers were identified through the Provincial Pediatric Oncology Registry, which includes data on demographics, disease treatment, and outcomes from each of Ontario’s five childhood cancer treatments centers.

Adolescents and young adults from 15 to 21 years who were treated at adult centers with adult regimens were identified through the Ontario Cancer Registry using chart abstraction by trained personnel at all treatment centers, with all data validated by clinician reviewers.

A total of 176 patients were identified, 129 with DLBCL and 47 with Burkitt’s lymphoma. In all, 62 of the 176 patients (35.2%) were treated in pediatric centers. Not surprisingly, multivariable analysis showed that AYA treated in adult centers were older, and more likely to have been treated earlier in the study period.

Comparing treatment patterns by locus of care, the investigators found that patients with DLBCL in pediatric centers received half of the cumulative anthracycline doses as those in adult centers (150 mg/m² vs. 300 mg/m²; P < .001) and about 75% of cumulative alkylating agent doses (3,300 mg/m² vs. 4,465 mg/m²; P = .009).

Patients with Burkitt’s lymphoma had identical exposures to anthracyclines in pediatric vs. adult centers (120 mg/m²), but those treated in pediatric centers had half the exposure to alkylators as those treated in adult centers (3,300 mg/m² vs. 6,600 mg/m²; P = .03).

Among patients with DLBCL, none of those treated at pediatric centers received rituximab, compared with 32.3% of those treated at adult centers (P < .001), whereas only a handful of patients with Burkitt’s lymphoma received rituximab in both pediatric and adult centers (nonsignificant).

Among all patients. 5-year event-free survival was 82.3% for those treated in pediatric centers, compared with 66.7% for those treated in adult centers (P = .02). Respective 5-year overall survival rates were 85.5% and 71.1% (P = .03).

Looking at survival by histology, the investigators saw that 5-year event-free survival for patients with DLBCL was 83.3% when they were treated like children vs. 66.7% when they were treated like adults (P = .04). Respective 5-year overall survival rates were 88.9% and 72% (P = .04).

Both event-free survival (80.8% vs. 66.7%) and overall survival (80.8% vs. 66.7%) were numerically but not statistically higher among patients with Burkitt’s treated at pediatric vs. adult centers.

An analysis adjusting for disease histology, stage, and time period of diagnosis showed that treatment at an adult center was associated with higher risk for death, with a hazard ratio of 2.4 (P = .03).

Additionally, an analysis adjusted for age, disease stage, and histology showed that patients treated in adult centers had a significantly increased risk of relapse or progression, compared with a HR of 4.4 (95% confidence interval; P = .008).

There were no significant differences in the risk of treatment-related mortality between the center types, however.

“It is important to note, however, that pediatric approaches to mature B-cell NHL [non-Hodgkin lymphoma] are associated with increased inpatient needs as compared to adult approaches, and with greater supportive care requirements. Thus the safety of such approaches in adults centers need to be established,” Dr. Gupta said.
 

Lower doses, better outcomes

In the question and answer session following the presentation, Jennifer Teichman, MD, MSc, a fellow in hematology at the University of Toronto who was not involved in the study asked why patients treated at adult centers would have higher relapse rates despite receiving higher doses of chemotherapy, noting that the poorer outcomes in those patients were not attributable to treatment-related mortality.

“I think one of the distinctions is that higher cumulative doses versus higher intensity of treatment over a shorter period of time are two different things, perhaps, and so giving lower cumulative doses but over a short period of time, and so giving higher intensity within that short period of time, may be what explains the higher success rate in pediatric trials,” Dr. Gupta said.

R. Michael Crump, MD, from the Princess Margaret Cancer Center, also in Toronto, asked whether the study results could have been influenced by differences between the pediatric center and adult center datasets in regard to pathology review, staging information, and International Prognostic Index.

Dr. Gupta acknowledged that, while the pediatric data were captured prospectively at each center by pediatric cancer registry staff and adult data were extracted retrospectively by trained chart reviewers, “the information that we were collecting was relatively basic – basic stage, basic histology, and that is a limitation.”

He also noted that clinicians reviewed the submitted retrospective data for completeness and had the ability to request chart extractors to return to a particular record for additional information or to correct potential errors.

The study was supported by the Canadian Institutes of Health Research, the C17 Council on Children’s Cancer & Blood Disorders, and the Pediatric Oncology Group of Ontario. Dr. Gupta, Dr. Teichman, and Dr. Crump all reported no relevant conflicts of interest.

SOURCE: Gupta S et al. ASH 2020, Abstract 708.

Adolescents and young adults with aggressive mature B-cell non-Hodgkin lymphomas appear to have better outcomes when they’re treated under pediatric protocols rather than adult regimens, Canadian investigators say.

Results of a study of patients from the ages of 15 to 21 years with either diffuse large B-cell lymphoma (DLBCL) or Burkitt’s lymphoma treated at regional or community cancer centers in the province of Ontario indicated that adolescents and young adult (AYA) patients treated at adult centers had a more than fourfold risk for disease relapse or progression, compared with their counterparts who were treated at pediatric centers, reported Sumit Gupta, MD, PhD, from the Hospital for Sick Children in Toronto and colleagues.

“Our data suggest that pediatric approaches are associated with improved event-free survival and overall survival, primarily due to a decrease in the risk of relapse or progression, while still using lower cumulative doses of chemotherapy,” he said in an oral abstract presented at the American Society of Hematology annual meeting, held virtually.

The findings echo those seen in the treatment of patients with acute lymphoblastic leukemia (ALL). As previously reported, a study from Nordic and Baltic countries showed that young adults with ALL who were treated with a pediatric regimen had a 4-year event-free survival rate of 73%, compared with 42% for historical controls.

Similarly, a prospective U.S. study reported in 2014 showed that AYA with ALL treated with a pediatric regimen had better overall and event-free survival rates, compared with historical controls.

As with ALL, pediatric and adult regimens for treatment of patients with aggressive mature B-cell NHL differ substantially, with pediatric patients receiving more intensive short-term therapy with lower cumulative doses.

In addition, while pediatric regimens for DLBCL and Burkitt’s lymphoma are identical, adult regimens differ substantially between the two histologies, Dr. Gupta pointed out.

Adult regimens for DLBCL most often incorporate CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or CHOP plus rituximab (R-CHOP), whereas Burkitt’s lymphoma in adults is generally treated with more aggressive multidrug regimens, in combination with rituximab.

Rituximab was incorporated into adults’ regimens far earlier than in pediatric regimens, with Food and Drug Administration approval of rituximab in frontline therapy of adults with DLBCL in 2006, “whereas the first pediatric large-scale randomized controlled trial of rituximab in pediatric mature B-cell lymphoma was only published earlier this year,” he noted.
 

Population-based study

To see how treatment patterns for AYA patients with aggressive mature B-cell non-Hodgkin lymphomas differ between pediatric and adult centers, Dr. Gupta and colleagues conducted a population-based study of all AYA in Ontario diagnosed with Burkitt’s or DLBCL from the ages of 15 to 21 years from 1992 through 2012.

AYA from the ages of 15 to 18 years who were treated at pediatric centers were identified through the Provincial Pediatric Oncology Registry, which includes data on demographics, disease treatment, and outcomes from each of Ontario’s five childhood cancer treatments centers.

Adolescents and young adults from 15 to 21 years who were treated at adult centers with adult regimens were identified through the Ontario Cancer Registry using chart abstraction by trained personnel at all treatment centers, with all data validated by clinician reviewers.

A total of 176 patients were identified, 129 with DLBCL and 47 with Burkitt’s lymphoma. In all, 62 of the 176 patients (35.2%) were treated in pediatric centers. Not surprisingly, multivariable analysis showed that AYA treated in adult centers were older, and more likely to have been treated earlier in the study period.

Comparing treatment patterns by locus of care, the investigators found that patients with DLBCL in pediatric centers received half of the cumulative anthracycline doses as those in adult centers (150 mg/m² vs. 300 mg/m²; P < .001) and about 75% of cumulative alkylating agent doses (3,300 mg/m² vs. 4,465 mg/m²; P = .009).

Patients with Burkitt’s lymphoma had identical exposures to anthracyclines in pediatric vs. adult centers (120 mg/m²), but those treated in pediatric centers had half the exposure to alkylators as those treated in adult centers (3,300 mg/m² vs. 6,600 mg/m²; P = .03).

Among patients with DLBCL, none of those treated at pediatric centers received rituximab, compared with 32.3% of those treated at adult centers (P < .001), whereas only a handful of patients with Burkitt’s lymphoma received rituximab in both pediatric and adult centers (nonsignificant).

Among all patients. 5-year event-free survival was 82.3% for those treated in pediatric centers, compared with 66.7% for those treated in adult centers (P = .02). Respective 5-year overall survival rates were 85.5% and 71.1% (P = .03).

Looking at survival by histology, the investigators saw that 5-year event-free survival for patients with DLBCL was 83.3% when they were treated like children vs. 66.7% when they were treated like adults (P = .04). Respective 5-year overall survival rates were 88.9% and 72% (P = .04).

Both event-free survival (80.8% vs. 66.7%) and overall survival (80.8% vs. 66.7%) were numerically but not statistically higher among patients with Burkitt’s treated at pediatric vs. adult centers.

An analysis adjusting for disease histology, stage, and time period of diagnosis showed that treatment at an adult center was associated with higher risk for death, with a hazard ratio of 2.4 (P = .03).

Additionally, an analysis adjusted for age, disease stage, and histology showed that patients treated in adult centers had a significantly increased risk of relapse or progression, compared with a HR of 4.4 (95% confidence interval; P = .008).

There were no significant differences in the risk of treatment-related mortality between the center types, however.

“It is important to note, however, that pediatric approaches to mature B-cell NHL [non-Hodgkin lymphoma] are associated with increased inpatient needs as compared to adult approaches, and with greater supportive care requirements. Thus the safety of such approaches in adults centers need to be established,” Dr. Gupta said.
 

Lower doses, better outcomes

In the question and answer session following the presentation, Jennifer Teichman, MD, MSc, a fellow in hematology at the University of Toronto who was not involved in the study asked why patients treated at adult centers would have higher relapse rates despite receiving higher doses of chemotherapy, noting that the poorer outcomes in those patients were not attributable to treatment-related mortality.

“I think one of the distinctions is that higher cumulative doses versus higher intensity of treatment over a shorter period of time are two different things, perhaps, and so giving lower cumulative doses but over a short period of time, and so giving higher intensity within that short period of time, may be what explains the higher success rate in pediatric trials,” Dr. Gupta said.

R. Michael Crump, MD, from the Princess Margaret Cancer Center, also in Toronto, asked whether the study results could have been influenced by differences between the pediatric center and adult center datasets in regard to pathology review, staging information, and International Prognostic Index.

Dr. Gupta acknowledged that, while the pediatric data were captured prospectively at each center by pediatric cancer registry staff and adult data were extracted retrospectively by trained chart reviewers, “the information that we were collecting was relatively basic – basic stage, basic histology, and that is a limitation.”

He also noted that clinicians reviewed the submitted retrospective data for completeness and had the ability to request chart extractors to return to a particular record for additional information or to correct potential errors.

The study was supported by the Canadian Institutes of Health Research, the C17 Council on Children’s Cancer & Blood Disorders, and the Pediatric Oncology Group of Ontario. Dr. Gupta, Dr. Teichman, and Dr. Crump all reported no relevant conflicts of interest.

SOURCE: Gupta S et al. ASH 2020, Abstract 708.

Adolescents and young adults with aggressive mature B-cell non-Hodgkin lymphomas appear to have better outcomes when they’re treated under pediatric protocols rather than adult regimens, Canadian investigators say.

Results of a study of patients from the ages of 15 to 21 years with either diffuse large B-cell lymphoma (DLBCL) or Burkitt’s lymphoma treated at regional or community cancer centers in the province of Ontario indicated that adolescents and young adult (AYA) patients treated at adult centers had a more than fourfold risk for disease relapse or progression, compared with their counterparts who were treated at pediatric centers, reported Sumit Gupta, MD, PhD, from the Hospital for Sick Children in Toronto and colleagues.

“Our data suggest that pediatric approaches are associated with improved event-free survival and overall survival, primarily due to a decrease in the risk of relapse or progression, while still using lower cumulative doses of chemotherapy,” he said in an oral abstract presented at the American Society of Hematology annual meeting, held virtually.

The findings echo those seen in the treatment of patients with acute lymphoblastic leukemia (ALL). As previously reported, a study from Nordic and Baltic countries showed that young adults with ALL who were treated with a pediatric regimen had a 4-year event-free survival rate of 73%, compared with 42% for historical controls.

Similarly, a prospective U.S. study reported in 2014 showed that AYA with ALL treated with a pediatric regimen had better overall and event-free survival rates, compared with historical controls.

As with ALL, pediatric and adult regimens for treatment of patients with aggressive mature B-cell NHL differ substantially, with pediatric patients receiving more intensive short-term therapy with lower cumulative doses.

In addition, while pediatric regimens for DLBCL and Burkitt’s lymphoma are identical, adult regimens differ substantially between the two histologies, Dr. Gupta pointed out.

Adult regimens for DLBCL most often incorporate CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or CHOP plus rituximab (R-CHOP), whereas Burkitt’s lymphoma in adults is generally treated with more aggressive multidrug regimens, in combination with rituximab.

Rituximab was incorporated into adults’ regimens far earlier than in pediatric regimens, with Food and Drug Administration approval of rituximab in frontline therapy of adults with DLBCL in 2006, “whereas the first pediatric large-scale randomized controlled trial of rituximab in pediatric mature B-cell lymphoma was only published earlier this year,” he noted.
 

Population-based study

To see how treatment patterns for AYA patients with aggressive mature B-cell non-Hodgkin lymphomas differ between pediatric and adult centers, Dr. Gupta and colleagues conducted a population-based study of all AYA in Ontario diagnosed with Burkitt’s or DLBCL from the ages of 15 to 21 years from 1992 through 2012.

AYA from the ages of 15 to 18 years who were treated at pediatric centers were identified through the Provincial Pediatric Oncology Registry, which includes data on demographics, disease treatment, and outcomes from each of Ontario’s five childhood cancer treatments centers.

Adolescents and young adults from 15 to 21 years who were treated at adult centers with adult regimens were identified through the Ontario Cancer Registry using chart abstraction by trained personnel at all treatment centers, with all data validated by clinician reviewers.

A total of 176 patients were identified, 129 with DLBCL and 47 with Burkitt’s lymphoma. In all, 62 of the 176 patients (35.2%) were treated in pediatric centers. Not surprisingly, multivariable analysis showed that AYA treated in adult centers were older, and more likely to have been treated earlier in the study period.

Comparing treatment patterns by locus of care, the investigators found that patients with DLBCL in pediatric centers received half of the cumulative anthracycline doses as those in adult centers (150 mg/m² vs. 300 mg/m²; P < .001) and about 75% of cumulative alkylating agent doses (3,300 mg/m² vs. 4,465 mg/m²; P = .009).

Patients with Burkitt’s lymphoma had identical exposures to anthracyclines in pediatric vs. adult centers (120 mg/m²), but those treated in pediatric centers had half the exposure to alkylators as those treated in adult centers (3,300 mg/m² vs. 6,600 mg/m²; P = .03).

Among patients with DLBCL, none of those treated at pediatric centers received rituximab, compared with 32.3% of those treated at adult centers (P < .001), whereas only a handful of patients with Burkitt’s lymphoma received rituximab in both pediatric and adult centers (nonsignificant).

Among all patients. 5-year event-free survival was 82.3% for those treated in pediatric centers, compared with 66.7% for those treated in adult centers (P = .02). Respective 5-year overall survival rates were 85.5% and 71.1% (P = .03).

Looking at survival by histology, the investigators saw that 5-year event-free survival for patients with DLBCL was 83.3% when they were treated like children vs. 66.7% when they were treated like adults (P = .04). Respective 5-year overall survival rates were 88.9% and 72% (P = .04).

Both event-free survival (80.8% vs. 66.7%) and overall survival (80.8% vs. 66.7%) were numerically but not statistically higher among patients with Burkitt’s treated at pediatric vs. adult centers.

An analysis adjusting for disease histology, stage, and time period of diagnosis showed that treatment at an adult center was associated with higher risk for death, with a hazard ratio of 2.4 (P = .03).

Additionally, an analysis adjusted for age, disease stage, and histology showed that patients treated in adult centers had a significantly increased risk of relapse or progression, compared with a HR of 4.4 (95% confidence interval; P = .008).

There were no significant differences in the risk of treatment-related mortality between the center types, however.

“It is important to note, however, that pediatric approaches to mature B-cell NHL [non-Hodgkin lymphoma] are associated with increased inpatient needs as compared to adult approaches, and with greater supportive care requirements. Thus the safety of such approaches in adults centers need to be established,” Dr. Gupta said.
 

Lower doses, better outcomes

In the question and answer session following the presentation, Jennifer Teichman, MD, MSc, a fellow in hematology at the University of Toronto who was not involved in the study asked why patients treated at adult centers would have higher relapse rates despite receiving higher doses of chemotherapy, noting that the poorer outcomes in those patients were not attributable to treatment-related mortality.

“I think one of the distinctions is that higher cumulative doses versus higher intensity of treatment over a shorter period of time are two different things, perhaps, and so giving lower cumulative doses but over a short period of time, and so giving higher intensity within that short period of time, may be what explains the higher success rate in pediatric trials,” Dr. Gupta said.

R. Michael Crump, MD, from the Princess Margaret Cancer Center, also in Toronto, asked whether the study results could have been influenced by differences between the pediatric center and adult center datasets in regard to pathology review, staging information, and International Prognostic Index.

Dr. Gupta acknowledged that, while the pediatric data were captured prospectively at each center by pediatric cancer registry staff and adult data were extracted retrospectively by trained chart reviewers, “the information that we were collecting was relatively basic – basic stage, basic histology, and that is a limitation.”

He also noted that clinicians reviewed the submitted retrospective data for completeness and had the ability to request chart extractors to return to a particular record for additional information or to correct potential errors.

The study was supported by the Canadian Institutes of Health Research, the C17 Council on Children’s Cancer & Blood Disorders, and the Pediatric Oncology Group of Ontario. Dr. Gupta, Dr. Teichman, and Dr. Crump all reported no relevant conflicts of interest.

SOURCE: Gupta S et al. ASH 2020, Abstract 708.