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Researchers tout new CLL prognostic tool
Researchers report that they’ve confirmed the usefulness of a new tool to help physicians pinpoint prognoses for patients with chronic lymphocytic leukemia (CLL).
“Physicians may use this tool to support decisions regarding supportive care, manage the patient’s and physician’s expectations, and potentially tailor therapy,” study lead author and epidemiologist Emelie Rotbain, MD, PhD, of Rigshospitalet in Copenhagen, said in an interview.
The study appeared Jan. 10 in the journal Blood Advances.
According to Dr. Rotbain,
Researchers developed the questions based on an analysis of categories in the Cumulative Illness Rating Scale that are most linked to event-free survival (EFS) from time of treatment.
The tool looks at three organ systems – vascular, upper GI, and endocrine – and asks about conditions such as diabetes and chronic use of a proton pump inhibitor, study coauthor and hematologist/oncologist Alexey V. Danilov, MD, PhD, codirector of the Toni Stephenson Lymphoma Center at the City of Hope National Medical Center, Duarte, Calif., said in an interview. The tool then generates a score based on the variables.
For the new study, the researchers retrospectively applied the tool to 4,975 patients who appeared in the Danish National CLL Register from 2008 to 2018 (61% male, median age 70.7.). Of those, 1,513 received first-line treatment during follow-up (median = 4.39 years).
At diagnosis, nearly two-thirds (63%) of patients were considered to be low risk. None of these had endocrinological, upper gastrointestinal, or vascular disease. Another 30% were considered to be at intermediate risk. The remaining 7% were at high risk. They had high levels of endocrinological (55.6%), upper gastrointestinal (64.6%), and vascular disease (91.0%).
The high-risk patients had a median survival of 6.0 years. The intermediate-risk patients lived for a median of 8.5 years, while the low-risk patients didn’t reach a median survival level.
Fifty-six percent of high-risk patients were treated within 4 years, compared to 20%-30% of intermediate- and low-risk patients. Median event-free survival from time of treatment was 8.4, 4.4, and 2.2 years for the low-, intermediate-, and high-risk groups, respectively.
The authors cautioned that “differences in survival by type of treatment, particularly in patients treated with targeted therapies who were underrepresented in this study, could influence survival and limit the generalizability of these results.”
They added that “while prognostic factors should remain key for treatment decisions, clinical trial data from pivotal phase 3 trials with novel targeted agents versus chemoimmunotherapy should be reanalyzed with addition of CLL-CI to assess the optimal treatment for patients according to CLL-CI.”
The tool is not yet available online, Dr. Danilov said, “but that is something that we as a group could potentially work on.”
Joanna Rhodes, MD, assistant professor with Northwell Health Cancer Institute/Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, N.Y., said in an interview that the tool is easy to use and appropriate to apply at first consultation. It should be used in conjunction with the International Prognostic Index for Chronic Lymphocytic Leukemia (CLL-IPI), she said.
“We often discuss frailty as a factor in types of and timing of treatment for patients with CLL, but often this is not directly measured in clinical practice,” she said. “The CLL-CI is associated with important outcomes, particularly overall survival, which is our most important metric in oncology. Additionally, it provides important information on time to first treatment and overall survival, which are useful when we are counseling patients.”
Like the study authors, Dr. Rhodes cautioned that the CLL-CI has not been validated specifically in patients treated with targeted therapies. “It may not be applicable in this setting, particularly in the front-line setting, as these treatments were underrepresented in this cohort. Further studies in this population are needed to answer this question.”
The study is funded in part by Novo Nordisk Foundation. Several study authors report various disclosures outside the scope of this study. Dr. Rhodes has no disclosures.
Researchers report that they’ve confirmed the usefulness of a new tool to help physicians pinpoint prognoses for patients with chronic lymphocytic leukemia (CLL).
“Physicians may use this tool to support decisions regarding supportive care, manage the patient’s and physician’s expectations, and potentially tailor therapy,” study lead author and epidemiologist Emelie Rotbain, MD, PhD, of Rigshospitalet in Copenhagen, said in an interview.
The study appeared Jan. 10 in the journal Blood Advances.
According to Dr. Rotbain,
Researchers developed the questions based on an analysis of categories in the Cumulative Illness Rating Scale that are most linked to event-free survival (EFS) from time of treatment.
The tool looks at three organ systems – vascular, upper GI, and endocrine – and asks about conditions such as diabetes and chronic use of a proton pump inhibitor, study coauthor and hematologist/oncologist Alexey V. Danilov, MD, PhD, codirector of the Toni Stephenson Lymphoma Center at the City of Hope National Medical Center, Duarte, Calif., said in an interview. The tool then generates a score based on the variables.
For the new study, the researchers retrospectively applied the tool to 4,975 patients who appeared in the Danish National CLL Register from 2008 to 2018 (61% male, median age 70.7.). Of those, 1,513 received first-line treatment during follow-up (median = 4.39 years).
At diagnosis, nearly two-thirds (63%) of patients were considered to be low risk. None of these had endocrinological, upper gastrointestinal, or vascular disease. Another 30% were considered to be at intermediate risk. The remaining 7% were at high risk. They had high levels of endocrinological (55.6%), upper gastrointestinal (64.6%), and vascular disease (91.0%).
The high-risk patients had a median survival of 6.0 years. The intermediate-risk patients lived for a median of 8.5 years, while the low-risk patients didn’t reach a median survival level.
Fifty-six percent of high-risk patients were treated within 4 years, compared to 20%-30% of intermediate- and low-risk patients. Median event-free survival from time of treatment was 8.4, 4.4, and 2.2 years for the low-, intermediate-, and high-risk groups, respectively.
The authors cautioned that “differences in survival by type of treatment, particularly in patients treated with targeted therapies who were underrepresented in this study, could influence survival and limit the generalizability of these results.”
They added that “while prognostic factors should remain key for treatment decisions, clinical trial data from pivotal phase 3 trials with novel targeted agents versus chemoimmunotherapy should be reanalyzed with addition of CLL-CI to assess the optimal treatment for patients according to CLL-CI.”
The tool is not yet available online, Dr. Danilov said, “but that is something that we as a group could potentially work on.”
Joanna Rhodes, MD, assistant professor with Northwell Health Cancer Institute/Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, N.Y., said in an interview that the tool is easy to use and appropriate to apply at first consultation. It should be used in conjunction with the International Prognostic Index for Chronic Lymphocytic Leukemia (CLL-IPI), she said.
“We often discuss frailty as a factor in types of and timing of treatment for patients with CLL, but often this is not directly measured in clinical practice,” she said. “The CLL-CI is associated with important outcomes, particularly overall survival, which is our most important metric in oncology. Additionally, it provides important information on time to first treatment and overall survival, which are useful when we are counseling patients.”
Like the study authors, Dr. Rhodes cautioned that the CLL-CI has not been validated specifically in patients treated with targeted therapies. “It may not be applicable in this setting, particularly in the front-line setting, as these treatments were underrepresented in this cohort. Further studies in this population are needed to answer this question.”
The study is funded in part by Novo Nordisk Foundation. Several study authors report various disclosures outside the scope of this study. Dr. Rhodes has no disclosures.
Researchers report that they’ve confirmed the usefulness of a new tool to help physicians pinpoint prognoses for patients with chronic lymphocytic leukemia (CLL).
“Physicians may use this tool to support decisions regarding supportive care, manage the patient’s and physician’s expectations, and potentially tailor therapy,” study lead author and epidemiologist Emelie Rotbain, MD, PhD, of Rigshospitalet in Copenhagen, said in an interview.
The study appeared Jan. 10 in the journal Blood Advances.
According to Dr. Rotbain,
Researchers developed the questions based on an analysis of categories in the Cumulative Illness Rating Scale that are most linked to event-free survival (EFS) from time of treatment.
The tool looks at three organ systems – vascular, upper GI, and endocrine – and asks about conditions such as diabetes and chronic use of a proton pump inhibitor, study coauthor and hematologist/oncologist Alexey V. Danilov, MD, PhD, codirector of the Toni Stephenson Lymphoma Center at the City of Hope National Medical Center, Duarte, Calif., said in an interview. The tool then generates a score based on the variables.
For the new study, the researchers retrospectively applied the tool to 4,975 patients who appeared in the Danish National CLL Register from 2008 to 2018 (61% male, median age 70.7.). Of those, 1,513 received first-line treatment during follow-up (median = 4.39 years).
At diagnosis, nearly two-thirds (63%) of patients were considered to be low risk. None of these had endocrinological, upper gastrointestinal, or vascular disease. Another 30% were considered to be at intermediate risk. The remaining 7% were at high risk. They had high levels of endocrinological (55.6%), upper gastrointestinal (64.6%), and vascular disease (91.0%).
The high-risk patients had a median survival of 6.0 years. The intermediate-risk patients lived for a median of 8.5 years, while the low-risk patients didn’t reach a median survival level.
Fifty-six percent of high-risk patients were treated within 4 years, compared to 20%-30% of intermediate- and low-risk patients. Median event-free survival from time of treatment was 8.4, 4.4, and 2.2 years for the low-, intermediate-, and high-risk groups, respectively.
The authors cautioned that “differences in survival by type of treatment, particularly in patients treated with targeted therapies who were underrepresented in this study, could influence survival and limit the generalizability of these results.”
They added that “while prognostic factors should remain key for treatment decisions, clinical trial data from pivotal phase 3 trials with novel targeted agents versus chemoimmunotherapy should be reanalyzed with addition of CLL-CI to assess the optimal treatment for patients according to CLL-CI.”
The tool is not yet available online, Dr. Danilov said, “but that is something that we as a group could potentially work on.”
Joanna Rhodes, MD, assistant professor with Northwell Health Cancer Institute/Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, N.Y., said in an interview that the tool is easy to use and appropriate to apply at first consultation. It should be used in conjunction with the International Prognostic Index for Chronic Lymphocytic Leukemia (CLL-IPI), she said.
“We often discuss frailty as a factor in types of and timing of treatment for patients with CLL, but often this is not directly measured in clinical practice,” she said. “The CLL-CI is associated with important outcomes, particularly overall survival, which is our most important metric in oncology. Additionally, it provides important information on time to first treatment and overall survival, which are useful when we are counseling patients.”
Like the study authors, Dr. Rhodes cautioned that the CLL-CI has not been validated specifically in patients treated with targeted therapies. “It may not be applicable in this setting, particularly in the front-line setting, as these treatments were underrepresented in this cohort. Further studies in this population are needed to answer this question.”
The study is funded in part by Novo Nordisk Foundation. Several study authors report various disclosures outside the scope of this study. Dr. Rhodes has no disclosures.
FROM BLOOD ADVANCES
Women at higher risk of serious adverse events from cancer therapy
and this is seen with chemotherapy, targeted agents, and especially with immunotherapy.
The finding comes from a review of more than 23,000 participants across 202 trials of various cancers (excluding sex-related cancers) that has been conducted over the past 40 years.
The investigators found a 34% increased risk of severe AEs among women, compared with men, climbing to a 49% higher risk with immunotherapy.
Women had a substantially greater risk of severe symptomatic AEs, including with immune checkpoint inhibitors and targeted tyrosine kinase inhibitors, and were more likely to experience severe hematologic AEs with chemotherapy and immunotherapy.
The particularly large sex differences with immunotherapy suggest “that studying AEs from these agents is a priority,” the investigators comment.
The article was published online on Feb. 4 in the Journal of Clinical Oncology.
“It has been understood that women have more toxicity from chemotherapy than men, but almost no research has aimed to understand whether that pattern held for novel treatments like immunotherapy or targeted therapies. We found similar large differences, especially for immune treatments,” said lead investigator Joseph Unger, PhD, a biostatistician and health services researcher at the Fred Hutchinson Cancer Research Center, Seattle, in an institutional press release.
A “better understanding of the nature of the underlying mechanisms could potentially lead to interventions or delivery modifications to reduce toxicity in women,” the investigators comment in their article.
Among a sea of possible explanations for the finding, there could be differences in how men and women metabolize cancer therapies or differences in how they perceive symptoms. Women may also receive relatively higher doses because of their body size or have higher adherence to treatment.
Whatever the case, as cancer treatment becomes increasingly individualized, “sex may be an important consideration,” Dr. Unger said.
Study details
The study involved 8,838 women and 14,458 men across the trials, which were phase 2 or 3 investigations conducted by the SWOG Cancer Research Network from 1980 to 2019. Trials including sex-related cancers were excluded. In the trials included in the review, the most common cancers were gastrointestinal and lung, followed by leukemia.
Seventy-five percent of the subjects received chemotherapy, and the rest received either targeted therapy or immunotherapy.
Two-thirds of the subjects had at least one grade 3 or higher AE; women had a 25% higher risk than men of having AEs of grade 5 or higher.
After adjusting for age, race, disease prognosis, and other factors, women were at increased risk of severe symptomatic AEs, such as nausea and pain, across all treatment lines and especially with immunotherapy, for which reports of symptomatic AEs were 66% higher.
Women also had a higher risk of symptomatic gastrointestinal AEs with all three treatments and a higher risk of sleep-related AEs with chemotherapy and immunotherapy, which “could be a function of hormonal effects interacting with cancer treatment,” the investigators said.
As for readily measurable AEs, women were at higher risk than men for objective hematologic AEs with chemotherapy, immunotherapy, and targeted therapy. There were no statistically significant sex differences in the risk of nonhematologic objective AEs.
The team notes that increased toxicity among women has been associated with improved survival, which may give AEs more time to develop. Higher rates of AEs might also signal increased delivery or efficacy of cancer treatments.
However, a previous study found that men may have a better response to immunotherapy than women. Immune checkpoint inhibitors were twice as effective as standard cancer therapies in the treatment of men with advanced solid tumors compared to their female counterparts, concluded a team that carried out a meta-analysis of 20 randomized controlled trials involving more than 11,351 patients.
The study was funded by the National Cancer Institute and others. Dr. Unger has disclosed no relevant financial relationships. Several coauthors have reported ties to a handful of companies, including Johnson & Johnson and Seattle Genetics. One is an employee of AIM Specialty Health.
A version of this article first appeared on Medscape.com.
and this is seen with chemotherapy, targeted agents, and especially with immunotherapy.
The finding comes from a review of more than 23,000 participants across 202 trials of various cancers (excluding sex-related cancers) that has been conducted over the past 40 years.
The investigators found a 34% increased risk of severe AEs among women, compared with men, climbing to a 49% higher risk with immunotherapy.
Women had a substantially greater risk of severe symptomatic AEs, including with immune checkpoint inhibitors and targeted tyrosine kinase inhibitors, and were more likely to experience severe hematologic AEs with chemotherapy and immunotherapy.
The particularly large sex differences with immunotherapy suggest “that studying AEs from these agents is a priority,” the investigators comment.
The article was published online on Feb. 4 in the Journal of Clinical Oncology.
“It has been understood that women have more toxicity from chemotherapy than men, but almost no research has aimed to understand whether that pattern held for novel treatments like immunotherapy or targeted therapies. We found similar large differences, especially for immune treatments,” said lead investigator Joseph Unger, PhD, a biostatistician and health services researcher at the Fred Hutchinson Cancer Research Center, Seattle, in an institutional press release.
A “better understanding of the nature of the underlying mechanisms could potentially lead to interventions or delivery modifications to reduce toxicity in women,” the investigators comment in their article.
Among a sea of possible explanations for the finding, there could be differences in how men and women metabolize cancer therapies or differences in how they perceive symptoms. Women may also receive relatively higher doses because of their body size or have higher adherence to treatment.
Whatever the case, as cancer treatment becomes increasingly individualized, “sex may be an important consideration,” Dr. Unger said.
Study details
The study involved 8,838 women and 14,458 men across the trials, which were phase 2 or 3 investigations conducted by the SWOG Cancer Research Network from 1980 to 2019. Trials including sex-related cancers were excluded. In the trials included in the review, the most common cancers were gastrointestinal and lung, followed by leukemia.
Seventy-five percent of the subjects received chemotherapy, and the rest received either targeted therapy or immunotherapy.
Two-thirds of the subjects had at least one grade 3 or higher AE; women had a 25% higher risk than men of having AEs of grade 5 or higher.
After adjusting for age, race, disease prognosis, and other factors, women were at increased risk of severe symptomatic AEs, such as nausea and pain, across all treatment lines and especially with immunotherapy, for which reports of symptomatic AEs were 66% higher.
Women also had a higher risk of symptomatic gastrointestinal AEs with all three treatments and a higher risk of sleep-related AEs with chemotherapy and immunotherapy, which “could be a function of hormonal effects interacting with cancer treatment,” the investigators said.
As for readily measurable AEs, women were at higher risk than men for objective hematologic AEs with chemotherapy, immunotherapy, and targeted therapy. There were no statistically significant sex differences in the risk of nonhematologic objective AEs.
The team notes that increased toxicity among women has been associated with improved survival, which may give AEs more time to develop. Higher rates of AEs might also signal increased delivery or efficacy of cancer treatments.
However, a previous study found that men may have a better response to immunotherapy than women. Immune checkpoint inhibitors were twice as effective as standard cancer therapies in the treatment of men with advanced solid tumors compared to their female counterparts, concluded a team that carried out a meta-analysis of 20 randomized controlled trials involving more than 11,351 patients.
The study was funded by the National Cancer Institute and others. Dr. Unger has disclosed no relevant financial relationships. Several coauthors have reported ties to a handful of companies, including Johnson & Johnson and Seattle Genetics. One is an employee of AIM Specialty Health.
A version of this article first appeared on Medscape.com.
and this is seen with chemotherapy, targeted agents, and especially with immunotherapy.
The finding comes from a review of more than 23,000 participants across 202 trials of various cancers (excluding sex-related cancers) that has been conducted over the past 40 years.
The investigators found a 34% increased risk of severe AEs among women, compared with men, climbing to a 49% higher risk with immunotherapy.
Women had a substantially greater risk of severe symptomatic AEs, including with immune checkpoint inhibitors and targeted tyrosine kinase inhibitors, and were more likely to experience severe hematologic AEs with chemotherapy and immunotherapy.
The particularly large sex differences with immunotherapy suggest “that studying AEs from these agents is a priority,” the investigators comment.
The article was published online on Feb. 4 in the Journal of Clinical Oncology.
“It has been understood that women have more toxicity from chemotherapy than men, but almost no research has aimed to understand whether that pattern held for novel treatments like immunotherapy or targeted therapies. We found similar large differences, especially for immune treatments,” said lead investigator Joseph Unger, PhD, a biostatistician and health services researcher at the Fred Hutchinson Cancer Research Center, Seattle, in an institutional press release.
A “better understanding of the nature of the underlying mechanisms could potentially lead to interventions or delivery modifications to reduce toxicity in women,” the investigators comment in their article.
Among a sea of possible explanations for the finding, there could be differences in how men and women metabolize cancer therapies or differences in how they perceive symptoms. Women may also receive relatively higher doses because of their body size or have higher adherence to treatment.
Whatever the case, as cancer treatment becomes increasingly individualized, “sex may be an important consideration,” Dr. Unger said.
Study details
The study involved 8,838 women and 14,458 men across the trials, which were phase 2 or 3 investigations conducted by the SWOG Cancer Research Network from 1980 to 2019. Trials including sex-related cancers were excluded. In the trials included in the review, the most common cancers were gastrointestinal and lung, followed by leukemia.
Seventy-five percent of the subjects received chemotherapy, and the rest received either targeted therapy or immunotherapy.
Two-thirds of the subjects had at least one grade 3 or higher AE; women had a 25% higher risk than men of having AEs of grade 5 or higher.
After adjusting for age, race, disease prognosis, and other factors, women were at increased risk of severe symptomatic AEs, such as nausea and pain, across all treatment lines and especially with immunotherapy, for which reports of symptomatic AEs were 66% higher.
Women also had a higher risk of symptomatic gastrointestinal AEs with all three treatments and a higher risk of sleep-related AEs with chemotherapy and immunotherapy, which “could be a function of hormonal effects interacting with cancer treatment,” the investigators said.
As for readily measurable AEs, women were at higher risk than men for objective hematologic AEs with chemotherapy, immunotherapy, and targeted therapy. There were no statistically significant sex differences in the risk of nonhematologic objective AEs.
The team notes that increased toxicity among women has been associated with improved survival, which may give AEs more time to develop. Higher rates of AEs might also signal increased delivery or efficacy of cancer treatments.
However, a previous study found that men may have a better response to immunotherapy than women. Immune checkpoint inhibitors were twice as effective as standard cancer therapies in the treatment of men with advanced solid tumors compared to their female counterparts, concluded a team that carried out a meta-analysis of 20 randomized controlled trials involving more than 11,351 patients.
The study was funded by the National Cancer Institute and others. Dr. Unger has disclosed no relevant financial relationships. Several coauthors have reported ties to a handful of companies, including Johnson & Johnson and Seattle Genetics. One is an employee of AIM Specialty Health.
A version of this article first appeared on Medscape.com.
Stopping venetoclax treatment early reduces CLL survival outcomes
“There’s not a lot of awareness about the fact that you’re probably better off not permanently discontinuing treatment,” Anthony R. Mato, first author of the research published in Haematologica, said in an interview.
“Instead, attempting dose reductions with later resumption to complete the planned schedule for treatment probably could improve outcomes,” said Dr. Mato, who is director of the CLL Program at Memorial Sloan Kettering Cancer Center in New York.
Venetoclax, a potent B-cell lymphoma-2 (BCL2) inhibitor, provides a novel, chemotherapy-free treatment option for first-line and r/r CLL. While its safety profile is manageable, treatment interruptions are very common, and premature discontinuations are reported in about a third of patients, often because of adverse events.
Lacking data on the effects of those interruptions on survival outcomes, Dr. Mato and colleagues conducted a post hoc analysis of the phase 3 MURANO trial. In this open-label study, treatment with six cycles of venetoclax in combination with rituximab followed by venetoclax once daily for a total of 2 years showed superior progression-free survival, compared with six cycles of bendamustine plus rituximab in patients with r/r CLL (P < .0001).
The current analysis involved 194 intention-to-treat patients from the trial’s venetoclax arm, among whom 140 (72%) completed 2 years of therapy, and 54 (28%) prematurely discontinued treatment. The most common reasons for discontinuation were adverse events (53.7%) and disease progression (22.2%).
Among those with early discontinuation for any reason except disease progression, the rate of progression-free survival was significantly inferior, compared with those who completed the treatment (hazard ratio, 5.98; P < .0001), as was the rate or discontinuation caused specifically by adverse events, which most commonly involved neutropenia or thrombocytopenia (HR, 5.82; P < .0001).
Those who discontinued had a mean duration of venetoclax therapy of 11.3 months, compared with 24.4 months for all patients. For each additional month of venetoclax therapy, there was a significantly lower risk of a progression-free survival event (P = .0263) and of an overall survival event (P < .0001).
The treatment interruption rate was much higher, at 69% (134), involving neutropenia in 43% (84) of instances and requiring dose reductions in 23% (45) of cases.
However, in contrast to permanent discontinuations, the temporary interruptions and dose reductions had no significant effect on progression-free or overall survival, regardless of the duration.
“Improved progression-free and overall survival were associated with greater cumulative venetoclax treatment exposure,” the authors wrote.
“The results of these analyses highlight the importance of appropriately managing treatment modifications to ensure optimal outcomes for patients receiving targeted treatment for CLL,” they said.
Key measures including “better supportive care, use of growth factors, and more aggressive strategies for dose reduction could potentially help to improve or decrease the number of patients discontinuing due to an adverse event,” Dr. Mato added.“We can’t say definitively because this is not a randomized study – it’s a retrospective analysis from a randomized study – but those measures likely could have a positive impact on patient outcomes.”
The study received support from Genentech and AbbVie. Dr. Mato reported consulting or other relationships with AbbVie, AstraZeneca, Celgene, DTRM, Genentech, Janssen, Loxo, PCYC, Sunesis, and TG Therapeutics.
“There’s not a lot of awareness about the fact that you’re probably better off not permanently discontinuing treatment,” Anthony R. Mato, first author of the research published in Haematologica, said in an interview.
“Instead, attempting dose reductions with later resumption to complete the planned schedule for treatment probably could improve outcomes,” said Dr. Mato, who is director of the CLL Program at Memorial Sloan Kettering Cancer Center in New York.
Venetoclax, a potent B-cell lymphoma-2 (BCL2) inhibitor, provides a novel, chemotherapy-free treatment option for first-line and r/r CLL. While its safety profile is manageable, treatment interruptions are very common, and premature discontinuations are reported in about a third of patients, often because of adverse events.
Lacking data on the effects of those interruptions on survival outcomes, Dr. Mato and colleagues conducted a post hoc analysis of the phase 3 MURANO trial. In this open-label study, treatment with six cycles of venetoclax in combination with rituximab followed by venetoclax once daily for a total of 2 years showed superior progression-free survival, compared with six cycles of bendamustine plus rituximab in patients with r/r CLL (P < .0001).
The current analysis involved 194 intention-to-treat patients from the trial’s venetoclax arm, among whom 140 (72%) completed 2 years of therapy, and 54 (28%) prematurely discontinued treatment. The most common reasons for discontinuation were adverse events (53.7%) and disease progression (22.2%).
Among those with early discontinuation for any reason except disease progression, the rate of progression-free survival was significantly inferior, compared with those who completed the treatment (hazard ratio, 5.98; P < .0001), as was the rate or discontinuation caused specifically by adverse events, which most commonly involved neutropenia or thrombocytopenia (HR, 5.82; P < .0001).
Those who discontinued had a mean duration of venetoclax therapy of 11.3 months, compared with 24.4 months for all patients. For each additional month of venetoclax therapy, there was a significantly lower risk of a progression-free survival event (P = .0263) and of an overall survival event (P < .0001).
The treatment interruption rate was much higher, at 69% (134), involving neutropenia in 43% (84) of instances and requiring dose reductions in 23% (45) of cases.
However, in contrast to permanent discontinuations, the temporary interruptions and dose reductions had no significant effect on progression-free or overall survival, regardless of the duration.
“Improved progression-free and overall survival were associated with greater cumulative venetoclax treatment exposure,” the authors wrote.
“The results of these analyses highlight the importance of appropriately managing treatment modifications to ensure optimal outcomes for patients receiving targeted treatment for CLL,” they said.
Key measures including “better supportive care, use of growth factors, and more aggressive strategies for dose reduction could potentially help to improve or decrease the number of patients discontinuing due to an adverse event,” Dr. Mato added.“We can’t say definitively because this is not a randomized study – it’s a retrospective analysis from a randomized study – but those measures likely could have a positive impact on patient outcomes.”
The study received support from Genentech and AbbVie. Dr. Mato reported consulting or other relationships with AbbVie, AstraZeneca, Celgene, DTRM, Genentech, Janssen, Loxo, PCYC, Sunesis, and TG Therapeutics.
“There’s not a lot of awareness about the fact that you’re probably better off not permanently discontinuing treatment,” Anthony R. Mato, first author of the research published in Haematologica, said in an interview.
“Instead, attempting dose reductions with later resumption to complete the planned schedule for treatment probably could improve outcomes,” said Dr. Mato, who is director of the CLL Program at Memorial Sloan Kettering Cancer Center in New York.
Venetoclax, a potent B-cell lymphoma-2 (BCL2) inhibitor, provides a novel, chemotherapy-free treatment option for first-line and r/r CLL. While its safety profile is manageable, treatment interruptions are very common, and premature discontinuations are reported in about a third of patients, often because of adverse events.
Lacking data on the effects of those interruptions on survival outcomes, Dr. Mato and colleagues conducted a post hoc analysis of the phase 3 MURANO trial. In this open-label study, treatment with six cycles of venetoclax in combination with rituximab followed by venetoclax once daily for a total of 2 years showed superior progression-free survival, compared with six cycles of bendamustine plus rituximab in patients with r/r CLL (P < .0001).
The current analysis involved 194 intention-to-treat patients from the trial’s venetoclax arm, among whom 140 (72%) completed 2 years of therapy, and 54 (28%) prematurely discontinued treatment. The most common reasons for discontinuation were adverse events (53.7%) and disease progression (22.2%).
Among those with early discontinuation for any reason except disease progression, the rate of progression-free survival was significantly inferior, compared with those who completed the treatment (hazard ratio, 5.98; P < .0001), as was the rate or discontinuation caused specifically by adverse events, which most commonly involved neutropenia or thrombocytopenia (HR, 5.82; P < .0001).
Those who discontinued had a mean duration of venetoclax therapy of 11.3 months, compared with 24.4 months for all patients. For each additional month of venetoclax therapy, there was a significantly lower risk of a progression-free survival event (P = .0263) and of an overall survival event (P < .0001).
The treatment interruption rate was much higher, at 69% (134), involving neutropenia in 43% (84) of instances and requiring dose reductions in 23% (45) of cases.
However, in contrast to permanent discontinuations, the temporary interruptions and dose reductions had no significant effect on progression-free or overall survival, regardless of the duration.
“Improved progression-free and overall survival were associated with greater cumulative venetoclax treatment exposure,” the authors wrote.
“The results of these analyses highlight the importance of appropriately managing treatment modifications to ensure optimal outcomes for patients receiving targeted treatment for CLL,” they said.
Key measures including “better supportive care, use of growth factors, and more aggressive strategies for dose reduction could potentially help to improve or decrease the number of patients discontinuing due to an adverse event,” Dr. Mato added.“We can’t say definitively because this is not a randomized study – it’s a retrospective analysis from a randomized study – but those measures likely could have a positive impact on patient outcomes.”
The study received support from Genentech and AbbVie. Dr. Mato reported consulting or other relationships with AbbVie, AstraZeneca, Celgene, DTRM, Genentech, Janssen, Loxo, PCYC, Sunesis, and TG Therapeutics.
FDA investigates possible increased risk of death with lymphoma drug
The FDA granted accelerated approval to umbralisib in February 2021 for patients with two types of lymphoma: Adults with relapsed or refractory marginal zone lymphoma who received at least one prior therapy, and those with relapsed or refractory follicular lymphoma who received at least three prior therapies.
According to the FDA, the possible increased risk of death arose from early findings in a phase 3 trial evaluating the drug in a related type of cancer: chronic lymphocytic leukemia.
“Because of the seriousness of this safety concern and the similarities between the two types of cancer for which this drug is approved and the type of cancer that was studied in the clinical trial, we are alerting patients and health care professionals that we are reevaluating this risk against the benefits of Ukoniq [umbralisib] for its approved uses,” the FDA safety communication states.
The FDA said it performed an initial review of data from the phase 3, randomized controlled UNITY trial, which is evaluating the efficacy of umbralisib plus a monoclonal antibody in patients with chronic lymphocytic leukemia.
“The results showed a possible increased risk of death in patients receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody compared to the control arm,” according to the FDA. “Those receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody also experienced more serious adverse events than those in the control arm.”
Although the drug has not been approved for patients with chronic lymphocytic leukemia, the FDA believes the findings could “have implications for its approved uses” in marginal zone lymphoma and follicular lymphoma.
However, the phase 2 trial that led to February 2021 approvals found the drug’s safety profile to be “manageable,” with serious adverse reactions reported in 18% of patients receiving the dual oral inhibitor of phosphoinositide 3 kinase delta and casein kinase 1 epsilon. These adverse reactions included diarrhea-colitis (4%), pneumonia (3%), sepsis (2%), and urinary tract infection (2%); however, no elevated risk of death was indicated in that analysis.
The FDA noted it will continue to evaluate the results from the phase 3 UNITY trial in chronic lymphocytic leukemia and has suspended enrollment of new patients in other ongoing clinical trials of the drug.
The FDA stated that it would communicate its “final conclusions and recommendations when we have completed our review.” In the meantime, the agency asks health care professionals to review how patients receiving umbralisib are faring and discuss “the risks and benefits of continuing” versus switching to other treatments.
The FDA also asks clinicians and patients to report side effects involving the drug to the FDA MedWatch program.
A version of this article first appeared on Medscape.com.
The FDA granted accelerated approval to umbralisib in February 2021 for patients with two types of lymphoma: Adults with relapsed or refractory marginal zone lymphoma who received at least one prior therapy, and those with relapsed or refractory follicular lymphoma who received at least three prior therapies.
According to the FDA, the possible increased risk of death arose from early findings in a phase 3 trial evaluating the drug in a related type of cancer: chronic lymphocytic leukemia.
“Because of the seriousness of this safety concern and the similarities between the two types of cancer for which this drug is approved and the type of cancer that was studied in the clinical trial, we are alerting patients and health care professionals that we are reevaluating this risk against the benefits of Ukoniq [umbralisib] for its approved uses,” the FDA safety communication states.
The FDA said it performed an initial review of data from the phase 3, randomized controlled UNITY trial, which is evaluating the efficacy of umbralisib plus a monoclonal antibody in patients with chronic lymphocytic leukemia.
“The results showed a possible increased risk of death in patients receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody compared to the control arm,” according to the FDA. “Those receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody also experienced more serious adverse events than those in the control arm.”
Although the drug has not been approved for patients with chronic lymphocytic leukemia, the FDA believes the findings could “have implications for its approved uses” in marginal zone lymphoma and follicular lymphoma.
However, the phase 2 trial that led to February 2021 approvals found the drug’s safety profile to be “manageable,” with serious adverse reactions reported in 18% of patients receiving the dual oral inhibitor of phosphoinositide 3 kinase delta and casein kinase 1 epsilon. These adverse reactions included diarrhea-colitis (4%), pneumonia (3%), sepsis (2%), and urinary tract infection (2%); however, no elevated risk of death was indicated in that analysis.
The FDA noted it will continue to evaluate the results from the phase 3 UNITY trial in chronic lymphocytic leukemia and has suspended enrollment of new patients in other ongoing clinical trials of the drug.
The FDA stated that it would communicate its “final conclusions and recommendations when we have completed our review.” In the meantime, the agency asks health care professionals to review how patients receiving umbralisib are faring and discuss “the risks and benefits of continuing” versus switching to other treatments.
The FDA also asks clinicians and patients to report side effects involving the drug to the FDA MedWatch program.
A version of this article first appeared on Medscape.com.
The FDA granted accelerated approval to umbralisib in February 2021 for patients with two types of lymphoma: Adults with relapsed or refractory marginal zone lymphoma who received at least one prior therapy, and those with relapsed or refractory follicular lymphoma who received at least three prior therapies.
According to the FDA, the possible increased risk of death arose from early findings in a phase 3 trial evaluating the drug in a related type of cancer: chronic lymphocytic leukemia.
“Because of the seriousness of this safety concern and the similarities between the two types of cancer for which this drug is approved and the type of cancer that was studied in the clinical trial, we are alerting patients and health care professionals that we are reevaluating this risk against the benefits of Ukoniq [umbralisib] for its approved uses,” the FDA safety communication states.
The FDA said it performed an initial review of data from the phase 3, randomized controlled UNITY trial, which is evaluating the efficacy of umbralisib plus a monoclonal antibody in patients with chronic lymphocytic leukemia.
“The results showed a possible increased risk of death in patients receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody compared to the control arm,” according to the FDA. “Those receiving the combination of Ukoniq [umbralisib] and the monoclonal antibody also experienced more serious adverse events than those in the control arm.”
Although the drug has not been approved for patients with chronic lymphocytic leukemia, the FDA believes the findings could “have implications for its approved uses” in marginal zone lymphoma and follicular lymphoma.
However, the phase 2 trial that led to February 2021 approvals found the drug’s safety profile to be “manageable,” with serious adverse reactions reported in 18% of patients receiving the dual oral inhibitor of phosphoinositide 3 kinase delta and casein kinase 1 epsilon. These adverse reactions included diarrhea-colitis (4%), pneumonia (3%), sepsis (2%), and urinary tract infection (2%); however, no elevated risk of death was indicated in that analysis.
The FDA noted it will continue to evaluate the results from the phase 3 UNITY trial in chronic lymphocytic leukemia and has suspended enrollment of new patients in other ongoing clinical trials of the drug.
The FDA stated that it would communicate its “final conclusions and recommendations when we have completed our review.” In the meantime, the agency asks health care professionals to review how patients receiving umbralisib are faring and discuss “the risks and benefits of continuing” versus switching to other treatments.
The FDA also asks clinicians and patients to report side effects involving the drug to the FDA MedWatch program.
A version of this article first appeared on Medscape.com.
CLL patients ‘cured’: 10 years post infusion, CAR T cells persist
“We can now conclude that CAR T cells can actually cure patients with leukemia based on these results,” said senior author Carl H. June, MD, in a press briefing on the study published in Nature.
“The major finding from this paper is that, 10 years down the road, you can find these [CAR T] cells,” Dr. June, director of the Center for Cellular Immunotherapies, University of Pennsylvania, Philadelphia, added. “The cells have evolved, and that was a big surprise ... but they are still able to kill leukemia cells 10 years after infusion.”
CAR T-cell therapy, in which patients’ own T cells are removed, reprogrammed in a lab to recognize and attack cancer cells, and then infused back into the patients, has transformed treatment of various blood cancers and shows often-remarkable results in achieving remissions.
While the treatment has become a routine therapy for certain leukemias, long-term results on the fate and function of the cells over time has been highly anticipated.
In the first published observations of a 10-year follow-up of patients treated with CAR T cells, Dr. June and colleagues described the findings for two patients, both with CLL, who back in 2010 were among the first to be treated with this groundbreaking therapy at the University of Pennsylvania.
A decade later, the CAR T cells are found to have remained detectable in both patients, who achieved complete remission in their first year of treatment, and both have sustained that remission.
Notably, the cells have evolved over the years – from initially being dominated by killer T cells to being dominated primarily by proliferative CD4-positive CAR T cells – with one of the patients exclusively having CD4-positive cells at year 9.3.
“The killer T cells did the initial heavy lifting of eliminating the tumor, “ first author J. Joseph Melenhorst, PhD, said in an interview.
“Once their job was done, those cells went down to very low levels, but the CD4-positive population persisted,” said Dr. Melenhorst, who established the lab at the University of Pennsylvania to follow patients treated with CAR T-cell therapy. “[This] delayed phase of immune response against cancer is a novel insight, and we were surprised to see it.”
Dr. Melenhorst noted that the clonal makeup of the CD4-positive cells importantly stabilized and became dominated by a small number of clones, suggesting further sustainability.
When one of the two patients, Doug Olson, who participated in the press conference, donated his cells back to the center after 9.3 years, the researchers found that his cells were still capable of destroying leukemia cells in the lab.
“Ten years [post infusion], we can’t find any of the leukemia cells and we still have the CAR T cells that are on patrol and on surveillance for residual leukemia,” Dr. June said.
One challenge of the otherwise desirable elimination of leukemia cells is that some aspects of sustaining CAR T-cell activity become problematic.
“The aspect of how the remission is maintained [is] very hard to study in a patient when there is no leukemia at all,” Dr. June explained. “It could be the last cell was gone within 3 weeks [of treatment], or it could be that the [cancer cells] are coming up like whack-a-moles, and they are killed because these CAR T cells are on patrol.”
Sadly, the other CLL patient, Bill Ludwig, who was first to receive the CAR T-cell treatment, died in 2021 from COVID-19.
Effects in other blood diseases similar?
CAR T-cell therapy is currently approved in the United States for several blood cancers, and whether similar long-term patterns of the cells may be observed in other patient and cancer types remains to be seen, Dr. Melenhorst said.
“I think in CLL we will see something similar, but in other diseases, we have yet to learn,” he said. “It may depend on issues including which domain has been engineered into the CAR.”
While the prospect of some patients being “cured” is exciting, responses to the therapy have generally been mixed. In CLL, for instance, full remissions have been observed to be maintained in about a quarter of patients, with higher rates observed in some lymphomas and pediatric ALL patients, Dr. Melenhorst explained.
The effects of CAR T-cell therapy in solid cancers have so far been more disappointing, with no research centers reproducing the kinds of results that have been seen with blood cancers.
“There appear to be a number of reasons, including that the [solid] tumor is more complex, and these solid cancers have ways to evade the immune system that need to be overcome,” Dr. June explained.
And despite the more encouraging findings in blood cancers, even with those, “the biggest disappointment is that CAR T-cell therapy doesn’t work all the time. It doesn’t work in every patient,” coauthor David Porter, MD, the University of Pennsylvania oncologist who treated the two patients, said in the press briefing.
“I think the importance of the Nature study is that we are starting to learn the mechanisms of why and how this works, so that we can start to get at how to make it work for more people,” Dr. Porter added. “But what we do see is that, when it works, it really is beyond what we expected 10 or 11 years ago.”
Speaking in the press briefing, Mr. Olson described how several weeks after his treatment in 2010, he became very ill with what has become known as the common, short-term side effect of cytokine release syndrome.
However, after Mr. Olson recovered a few days later, Dr. Porter gave him the remarkable news that “we cannot find a single cancer cell. You appear completely free of CLL.”
Mr. Olson reported that he has since lived a “full life,” kept working, and has even run some half-marathons.
Dr. June confided that the current 10-year results far exceed the team’s early expectations for CAR T-cell therapy. “After Doug [initially] signed his informed consent document for this, we thought that the cells would all be gone within a month or 2. The fact that they have survived for 10 years was a major surprise – and a happy one at that.”
Dr. June, Dr. Melenhorst, and Dr. Porter reported holding patents related to CAR T-cell manufacturing and biomarker discovery.
“We can now conclude that CAR T cells can actually cure patients with leukemia based on these results,” said senior author Carl H. June, MD, in a press briefing on the study published in Nature.
“The major finding from this paper is that, 10 years down the road, you can find these [CAR T] cells,” Dr. June, director of the Center for Cellular Immunotherapies, University of Pennsylvania, Philadelphia, added. “The cells have evolved, and that was a big surprise ... but they are still able to kill leukemia cells 10 years after infusion.”
CAR T-cell therapy, in which patients’ own T cells are removed, reprogrammed in a lab to recognize and attack cancer cells, and then infused back into the patients, has transformed treatment of various blood cancers and shows often-remarkable results in achieving remissions.
While the treatment has become a routine therapy for certain leukemias, long-term results on the fate and function of the cells over time has been highly anticipated.
In the first published observations of a 10-year follow-up of patients treated with CAR T cells, Dr. June and colleagues described the findings for two patients, both with CLL, who back in 2010 were among the first to be treated with this groundbreaking therapy at the University of Pennsylvania.
A decade later, the CAR T cells are found to have remained detectable in both patients, who achieved complete remission in their first year of treatment, and both have sustained that remission.
Notably, the cells have evolved over the years – from initially being dominated by killer T cells to being dominated primarily by proliferative CD4-positive CAR T cells – with one of the patients exclusively having CD4-positive cells at year 9.3.
“The killer T cells did the initial heavy lifting of eliminating the tumor, “ first author J. Joseph Melenhorst, PhD, said in an interview.
“Once their job was done, those cells went down to very low levels, but the CD4-positive population persisted,” said Dr. Melenhorst, who established the lab at the University of Pennsylvania to follow patients treated with CAR T-cell therapy. “[This] delayed phase of immune response against cancer is a novel insight, and we were surprised to see it.”
Dr. Melenhorst noted that the clonal makeup of the CD4-positive cells importantly stabilized and became dominated by a small number of clones, suggesting further sustainability.
When one of the two patients, Doug Olson, who participated in the press conference, donated his cells back to the center after 9.3 years, the researchers found that his cells were still capable of destroying leukemia cells in the lab.
“Ten years [post infusion], we can’t find any of the leukemia cells and we still have the CAR T cells that are on patrol and on surveillance for residual leukemia,” Dr. June said.
One challenge of the otherwise desirable elimination of leukemia cells is that some aspects of sustaining CAR T-cell activity become problematic.
“The aspect of how the remission is maintained [is] very hard to study in a patient when there is no leukemia at all,” Dr. June explained. “It could be the last cell was gone within 3 weeks [of treatment], or it could be that the [cancer cells] are coming up like whack-a-moles, and they are killed because these CAR T cells are on patrol.”
Sadly, the other CLL patient, Bill Ludwig, who was first to receive the CAR T-cell treatment, died in 2021 from COVID-19.
Effects in other blood diseases similar?
CAR T-cell therapy is currently approved in the United States for several blood cancers, and whether similar long-term patterns of the cells may be observed in other patient and cancer types remains to be seen, Dr. Melenhorst said.
“I think in CLL we will see something similar, but in other diseases, we have yet to learn,” he said. “It may depend on issues including which domain has been engineered into the CAR.”
While the prospect of some patients being “cured” is exciting, responses to the therapy have generally been mixed. In CLL, for instance, full remissions have been observed to be maintained in about a quarter of patients, with higher rates observed in some lymphomas and pediatric ALL patients, Dr. Melenhorst explained.
The effects of CAR T-cell therapy in solid cancers have so far been more disappointing, with no research centers reproducing the kinds of results that have been seen with blood cancers.
“There appear to be a number of reasons, including that the [solid] tumor is more complex, and these solid cancers have ways to evade the immune system that need to be overcome,” Dr. June explained.
And despite the more encouraging findings in blood cancers, even with those, “the biggest disappointment is that CAR T-cell therapy doesn’t work all the time. It doesn’t work in every patient,” coauthor David Porter, MD, the University of Pennsylvania oncologist who treated the two patients, said in the press briefing.
“I think the importance of the Nature study is that we are starting to learn the mechanisms of why and how this works, so that we can start to get at how to make it work for more people,” Dr. Porter added. “But what we do see is that, when it works, it really is beyond what we expected 10 or 11 years ago.”
Speaking in the press briefing, Mr. Olson described how several weeks after his treatment in 2010, he became very ill with what has become known as the common, short-term side effect of cytokine release syndrome.
However, after Mr. Olson recovered a few days later, Dr. Porter gave him the remarkable news that “we cannot find a single cancer cell. You appear completely free of CLL.”
Mr. Olson reported that he has since lived a “full life,” kept working, and has even run some half-marathons.
Dr. June confided that the current 10-year results far exceed the team’s early expectations for CAR T-cell therapy. “After Doug [initially] signed his informed consent document for this, we thought that the cells would all be gone within a month or 2. The fact that they have survived for 10 years was a major surprise – and a happy one at that.”
Dr. June, Dr. Melenhorst, and Dr. Porter reported holding patents related to CAR T-cell manufacturing and biomarker discovery.
“We can now conclude that CAR T cells can actually cure patients with leukemia based on these results,” said senior author Carl H. June, MD, in a press briefing on the study published in Nature.
“The major finding from this paper is that, 10 years down the road, you can find these [CAR T] cells,” Dr. June, director of the Center for Cellular Immunotherapies, University of Pennsylvania, Philadelphia, added. “The cells have evolved, and that was a big surprise ... but they are still able to kill leukemia cells 10 years after infusion.”
CAR T-cell therapy, in which patients’ own T cells are removed, reprogrammed in a lab to recognize and attack cancer cells, and then infused back into the patients, has transformed treatment of various blood cancers and shows often-remarkable results in achieving remissions.
While the treatment has become a routine therapy for certain leukemias, long-term results on the fate and function of the cells over time has been highly anticipated.
In the first published observations of a 10-year follow-up of patients treated with CAR T cells, Dr. June and colleagues described the findings for two patients, both with CLL, who back in 2010 were among the first to be treated with this groundbreaking therapy at the University of Pennsylvania.
A decade later, the CAR T cells are found to have remained detectable in both patients, who achieved complete remission in their first year of treatment, and both have sustained that remission.
Notably, the cells have evolved over the years – from initially being dominated by killer T cells to being dominated primarily by proliferative CD4-positive CAR T cells – with one of the patients exclusively having CD4-positive cells at year 9.3.
“The killer T cells did the initial heavy lifting of eliminating the tumor, “ first author J. Joseph Melenhorst, PhD, said in an interview.
“Once their job was done, those cells went down to very low levels, but the CD4-positive population persisted,” said Dr. Melenhorst, who established the lab at the University of Pennsylvania to follow patients treated with CAR T-cell therapy. “[This] delayed phase of immune response against cancer is a novel insight, and we were surprised to see it.”
Dr. Melenhorst noted that the clonal makeup of the CD4-positive cells importantly stabilized and became dominated by a small number of clones, suggesting further sustainability.
When one of the two patients, Doug Olson, who participated in the press conference, donated his cells back to the center after 9.3 years, the researchers found that his cells were still capable of destroying leukemia cells in the lab.
“Ten years [post infusion], we can’t find any of the leukemia cells and we still have the CAR T cells that are on patrol and on surveillance for residual leukemia,” Dr. June said.
One challenge of the otherwise desirable elimination of leukemia cells is that some aspects of sustaining CAR T-cell activity become problematic.
“The aspect of how the remission is maintained [is] very hard to study in a patient when there is no leukemia at all,” Dr. June explained. “It could be the last cell was gone within 3 weeks [of treatment], or it could be that the [cancer cells] are coming up like whack-a-moles, and they are killed because these CAR T cells are on patrol.”
Sadly, the other CLL patient, Bill Ludwig, who was first to receive the CAR T-cell treatment, died in 2021 from COVID-19.
Effects in other blood diseases similar?
CAR T-cell therapy is currently approved in the United States for several blood cancers, and whether similar long-term patterns of the cells may be observed in other patient and cancer types remains to be seen, Dr. Melenhorst said.
“I think in CLL we will see something similar, but in other diseases, we have yet to learn,” he said. “It may depend on issues including which domain has been engineered into the CAR.”
While the prospect of some patients being “cured” is exciting, responses to the therapy have generally been mixed. In CLL, for instance, full remissions have been observed to be maintained in about a quarter of patients, with higher rates observed in some lymphomas and pediatric ALL patients, Dr. Melenhorst explained.
The effects of CAR T-cell therapy in solid cancers have so far been more disappointing, with no research centers reproducing the kinds of results that have been seen with blood cancers.
“There appear to be a number of reasons, including that the [solid] tumor is more complex, and these solid cancers have ways to evade the immune system that need to be overcome,” Dr. June explained.
And despite the more encouraging findings in blood cancers, even with those, “the biggest disappointment is that CAR T-cell therapy doesn’t work all the time. It doesn’t work in every patient,” coauthor David Porter, MD, the University of Pennsylvania oncologist who treated the two patients, said in the press briefing.
“I think the importance of the Nature study is that we are starting to learn the mechanisms of why and how this works, so that we can start to get at how to make it work for more people,” Dr. Porter added. “But what we do see is that, when it works, it really is beyond what we expected 10 or 11 years ago.”
Speaking in the press briefing, Mr. Olson described how several weeks after his treatment in 2010, he became very ill with what has become known as the common, short-term side effect of cytokine release syndrome.
However, after Mr. Olson recovered a few days later, Dr. Porter gave him the remarkable news that “we cannot find a single cancer cell. You appear completely free of CLL.”
Mr. Olson reported that he has since lived a “full life,” kept working, and has even run some half-marathons.
Dr. June confided that the current 10-year results far exceed the team’s early expectations for CAR T-cell therapy. “After Doug [initially] signed his informed consent document for this, we thought that the cells would all be gone within a month or 2. The fact that they have survived for 10 years was a major surprise – and a happy one at that.”
Dr. June, Dr. Melenhorst, and Dr. Porter reported holding patents related to CAR T-cell manufacturing and biomarker discovery.
FROM NATURE
100 coauthored papers, 10 years: Cancer transplant pioneers model 'team science'
On July 29, 2021, Sergio Giralt, MD, deputy division head of the division of hematologic malignancies and Miguel-Angel Perales, MD, chief of the adult bone marrow transplant service at MSKCC, published their 100th peer-reviewed paper as coauthors. Listing hundreds of such articles on a CV is standard for top-tier physicians, but the pair had gone one better: 100 publications written together in 10 years.
Their centenary article hit scientific newsstands almost exactly a decade after their first joint paper, which appeared in September 2011, not long after they met.
Born in Cuba, Dr. Giralt grew up in Venezuela. From the age of 14, he knew that medicine was his path, and in 1984 he earned a medical degree from the Universidad Central de Venezuela, Caracas. Next came a research position at Harvard Medical School, a residency at the Good Samaritan Hospital, Cincinnati, and a fellowship at the University of Texas MD Anderson Cancer Center, Houston. Dr. Giralt arrived at MSKCC in 2010 as the new chief of the adult bone marrow transplant service. There he was introduced to a new colleague, Dr. Perales. They soon learned that in addition to expertise in hematology, they had second language in common: Spanish.
Dr. Giralt said: “We both have a Spanish background and in a certain sense, there was an affinity there. ... We both have shared experiences.”
Dr. Perales was brought up in Belgium, a European nation with three official languages: French, Dutch, and German. He speaks five tongues in all and learned Spanish from his father, who came from Spain.
Fluency in Spanish enables both physicians to take care of the many New Yorkers who are more comfortable in that language – especially when navigating cancer treatment. However, both Dr. Giralt and Dr. Perales said that a second language is more than a professional tool. They described the enjoyable change of persona that happens when they switch to Spanish.
“People who are multilingual have different roles [as much as] different languages,” said Dr. Perales. “When I’m in Spanish, part of my brain is [thinking back to] summer vacations and hanging out with my cousins.”
When it comes to clinical science, however, English is the language of choice.
Global leaders in HSCT
Dr. Giralt and Dr. Perales are known worldwide in the field of allogeneic HSCT, a potentially curative treatment for an elongating list of both malignant and nonmalignant diseases.
In 1973, MSKCC conducted the first bone-marrow transplant from an unrelated donor. Fifty years on, medical oncologists in the United States conduct approximately 8,500 allogeneic transplants each year, 72% to treat acute leukemias or myelodysplastic syndrome (MDS).
However, stripping the immune system with intensive chemotherapy ‘conditioning,’ then rebuilding it with non-diseased donor hematopoietic cells is a hazardous undertaking. Older patients are less likely to survive the intensive conditioning, so historically have missed out. Also, even with a good human leukocyte antigen (HLA) match, the recipient needs often brutal immunosuppression.
Since Dr. Giralt and Dr. Perales began their partnership in 2010, the goals of their work have not changed: to develop safer, lower-intensity transplantation suitable for older, more vulnerable patients and reduce fearsome posttransplant sequelae such as graft-versus-host disease (GVHD).
Dr. Giralt’s publication list spans more than 600 peer-reviewed papers, articles and book chapters, almost exclusively on HSCT. Dr. Perales has more than 300 publication credits on the topic.
The two paired up on their first paper just months after Dr. Giralt arrived at MSKCC. That article, published in Biology of Blood and Marrow Transplantation, compared umbilical cord blood for HSCT with donor blood in 367 people with a variety of hematologic malignancies, including acute and chronic leukemias, MDS, and lymphoma.
The MSKCC team found that transplant-related mortality in the first 180 days was higher for the cord blood (21%), but thereafter mortality and relapse were much lower than for donated blood, with the result that 2-year progression-free survival of 55% was similar. Dr. Perales, Dr. Giralt and their coauthors concluded that the data provided “strong support” for further work on cord blood as an alternative stem-cell source.
During their first decade of collaboration, Dr. Giralt and Dr. Perales worked on any promising avenue that could improve outcomes and the experience of HSCT recipients, including reduced-intensity conditioning regimens to allow older adults to benefit from curative HSCT and donor T-cell depletion by CD34 selection, to reduce graft-versus-host disease (GVHD).
The CD34 protein is typically found on the surface of early stage and highly active stem cell types. Selecting these cell types using a range of techniques can eliminate many other potentially interfering or inactive cells. This enriches the transplant population with the most effective cells and can lower the risk of GVHD.
The 100th paper on which Dr. Giralt and Dr. Perales were coauthors was published in Blood Advances on July 27, 2021. The retrospective study examined the fate of 58 MSKCC patients with a rare form of chronic lymphocytic leukemia, CLL with Richter’s transformation (CLL-RT). It was the largest such study to date of this rare disease.
M.D. Anderson Cancer Center had shown in 2006 that, despite chemotherapy, overall survival in patients with CLL-RT was approximately 8 months. HSCT improved survival dramatically (75% at 3 years; n = 7). However, with the advent of novel targeted drugs for CLL such as ibrutinib (Imbruvica), venetoclax (Venclexta), or idelalisib (Zydelig), the MSKCC team asked themselves: What was the role of reduced-intensive conditioning HSCT? Was it even safe? Among other findings, Dr. Giralt and Dr. Perales’ 100th paper showed that reduced-intensity HSCT remained a viable alternative after a CLL-RT patient progressed on a novel agent.
Impact of the pandemic
When COVID-19 hit, the team lost many research staff and developed a huge backlog, said Dr. Giralt. He and Dr. Perales realized that they needed to be “thoughtful and careful” about which studies to continue. “For example, the CD-34 selection trials we did not close because these are our workhorse trials,” Dr. Giralt said. “We have people we need to treat, and some of the patients that we need to treat can only be treated on trial.”
The team was also able to pivot some of their work into COVID 19 itself, and they collected crucial information on HSCT in recovered COVID-19 patients, as an example.
“We were living through a critical time, but that doesn’t mean we [aren’t] obligated to continue our mission, our research mission,” said Dr. Giralt. “It really is team science. The way we look at it ... there’s a common thread: We both like to do allogeneic transplant, and we both believe in trying to make CD-34 selection better. So we’re both very much [working on] how can we improve what we call ‘the Memorial way’ of doing transplants. Where we separate is, Miguel does primarily lymphoma. He doesn’t do myeloma [like me]. So in those two areas, we’re helping develop the junior faculty in a different way.”
Something more in common
Right from the start, Dr. Perales and Dr. Giralt also shared a commitment to mentoring. Since 2010, Dr. Perales has mentored 22 up-and-coming junior faculty, including 10 from Europe (8 from Spain) and 2 from Latin America.
“[It makes] the research enterprise much more productive but [these young scientists] really increase the visibility of the program,” said Dr. Giralt.
He cited Dr. Perales’ track record of mentoring as one of the reasons for his promotion to chief of the adult bone marrow transplant service. In March 2020, Dr. Perales seamlessly stepped into Dr. Giralt’s shoes, while Dr. Giralt moved on to his present role as deputy division head of the division of hematologic malignancies.
Dr. Perales said: “The key aspect [of these promotions] is the fantastic working relationship that we’ve had over the years. ... I consider Sergio my mentor, but also a good friend and colleague. And so I think it’s this ability that we’ve had to work together and that relationship of trust, which has been key.”
“Sergio is somebody who lifts people up,” Dr. Perales added. “Many people will tell you that Sergio has helped them in their career. ... And I think that’s a lesson I’ve learned from him: training the next generation. And [that’s] not just in the U.S., but outside. I think that’s a key role that we have. And our responsibility.”
Asked to comment on their 100th-paper milestone, Dr. Perales firmly turned the spotlight from himself and Dr. Giralt to the junior investigators who have passed through the doors of the bone-marrow transplant program: “This body of work represents not just our collaboration but also the many contributions of our team at MSK ... and beyond MSK.”
This article was updated 1/26/22.
On July 29, 2021, Sergio Giralt, MD, deputy division head of the division of hematologic malignancies and Miguel-Angel Perales, MD, chief of the adult bone marrow transplant service at MSKCC, published their 100th peer-reviewed paper as coauthors. Listing hundreds of such articles on a CV is standard for top-tier physicians, but the pair had gone one better: 100 publications written together in 10 years.
Their centenary article hit scientific newsstands almost exactly a decade after their first joint paper, which appeared in September 2011, not long after they met.
Born in Cuba, Dr. Giralt grew up in Venezuela. From the age of 14, he knew that medicine was his path, and in 1984 he earned a medical degree from the Universidad Central de Venezuela, Caracas. Next came a research position at Harvard Medical School, a residency at the Good Samaritan Hospital, Cincinnati, and a fellowship at the University of Texas MD Anderson Cancer Center, Houston. Dr. Giralt arrived at MSKCC in 2010 as the new chief of the adult bone marrow transplant service. There he was introduced to a new colleague, Dr. Perales. They soon learned that in addition to expertise in hematology, they had second language in common: Spanish.
Dr. Giralt said: “We both have a Spanish background and in a certain sense, there was an affinity there. ... We both have shared experiences.”
Dr. Perales was brought up in Belgium, a European nation with three official languages: French, Dutch, and German. He speaks five tongues in all and learned Spanish from his father, who came from Spain.
Fluency in Spanish enables both physicians to take care of the many New Yorkers who are more comfortable in that language – especially when navigating cancer treatment. However, both Dr. Giralt and Dr. Perales said that a second language is more than a professional tool. They described the enjoyable change of persona that happens when they switch to Spanish.
“People who are multilingual have different roles [as much as] different languages,” said Dr. Perales. “When I’m in Spanish, part of my brain is [thinking back to] summer vacations and hanging out with my cousins.”
When it comes to clinical science, however, English is the language of choice.
Global leaders in HSCT
Dr. Giralt and Dr. Perales are known worldwide in the field of allogeneic HSCT, a potentially curative treatment for an elongating list of both malignant and nonmalignant diseases.
In 1973, MSKCC conducted the first bone-marrow transplant from an unrelated donor. Fifty years on, medical oncologists in the United States conduct approximately 8,500 allogeneic transplants each year, 72% to treat acute leukemias or myelodysplastic syndrome (MDS).
However, stripping the immune system with intensive chemotherapy ‘conditioning,’ then rebuilding it with non-diseased donor hematopoietic cells is a hazardous undertaking. Older patients are less likely to survive the intensive conditioning, so historically have missed out. Also, even with a good human leukocyte antigen (HLA) match, the recipient needs often brutal immunosuppression.
Since Dr. Giralt and Dr. Perales began their partnership in 2010, the goals of their work have not changed: to develop safer, lower-intensity transplantation suitable for older, more vulnerable patients and reduce fearsome posttransplant sequelae such as graft-versus-host disease (GVHD).
Dr. Giralt’s publication list spans more than 600 peer-reviewed papers, articles and book chapters, almost exclusively on HSCT. Dr. Perales has more than 300 publication credits on the topic.
The two paired up on their first paper just months after Dr. Giralt arrived at MSKCC. That article, published in Biology of Blood and Marrow Transplantation, compared umbilical cord blood for HSCT with donor blood in 367 people with a variety of hematologic malignancies, including acute and chronic leukemias, MDS, and lymphoma.
The MSKCC team found that transplant-related mortality in the first 180 days was higher for the cord blood (21%), but thereafter mortality and relapse were much lower than for donated blood, with the result that 2-year progression-free survival of 55% was similar. Dr. Perales, Dr. Giralt and their coauthors concluded that the data provided “strong support” for further work on cord blood as an alternative stem-cell source.
During their first decade of collaboration, Dr. Giralt and Dr. Perales worked on any promising avenue that could improve outcomes and the experience of HSCT recipients, including reduced-intensity conditioning regimens to allow older adults to benefit from curative HSCT and donor T-cell depletion by CD34 selection, to reduce graft-versus-host disease (GVHD).
The CD34 protein is typically found on the surface of early stage and highly active stem cell types. Selecting these cell types using a range of techniques can eliminate many other potentially interfering or inactive cells. This enriches the transplant population with the most effective cells and can lower the risk of GVHD.
The 100th paper on which Dr. Giralt and Dr. Perales were coauthors was published in Blood Advances on July 27, 2021. The retrospective study examined the fate of 58 MSKCC patients with a rare form of chronic lymphocytic leukemia, CLL with Richter’s transformation (CLL-RT). It was the largest such study to date of this rare disease.
M.D. Anderson Cancer Center had shown in 2006 that, despite chemotherapy, overall survival in patients with CLL-RT was approximately 8 months. HSCT improved survival dramatically (75% at 3 years; n = 7). However, with the advent of novel targeted drugs for CLL such as ibrutinib (Imbruvica), venetoclax (Venclexta), or idelalisib (Zydelig), the MSKCC team asked themselves: What was the role of reduced-intensive conditioning HSCT? Was it even safe? Among other findings, Dr. Giralt and Dr. Perales’ 100th paper showed that reduced-intensity HSCT remained a viable alternative after a CLL-RT patient progressed on a novel agent.
Impact of the pandemic
When COVID-19 hit, the team lost many research staff and developed a huge backlog, said Dr. Giralt. He and Dr. Perales realized that they needed to be “thoughtful and careful” about which studies to continue. “For example, the CD-34 selection trials we did not close because these are our workhorse trials,” Dr. Giralt said. “We have people we need to treat, and some of the patients that we need to treat can only be treated on trial.”
The team was also able to pivot some of their work into COVID 19 itself, and they collected crucial information on HSCT in recovered COVID-19 patients, as an example.
“We were living through a critical time, but that doesn’t mean we [aren’t] obligated to continue our mission, our research mission,” said Dr. Giralt. “It really is team science. The way we look at it ... there’s a common thread: We both like to do allogeneic transplant, and we both believe in trying to make CD-34 selection better. So we’re both very much [working on] how can we improve what we call ‘the Memorial way’ of doing transplants. Where we separate is, Miguel does primarily lymphoma. He doesn’t do myeloma [like me]. So in those two areas, we’re helping develop the junior faculty in a different way.”
Something more in common
Right from the start, Dr. Perales and Dr. Giralt also shared a commitment to mentoring. Since 2010, Dr. Perales has mentored 22 up-and-coming junior faculty, including 10 from Europe (8 from Spain) and 2 from Latin America.
“[It makes] the research enterprise much more productive but [these young scientists] really increase the visibility of the program,” said Dr. Giralt.
He cited Dr. Perales’ track record of mentoring as one of the reasons for his promotion to chief of the adult bone marrow transplant service. In March 2020, Dr. Perales seamlessly stepped into Dr. Giralt’s shoes, while Dr. Giralt moved on to his present role as deputy division head of the division of hematologic malignancies.
Dr. Perales said: “The key aspect [of these promotions] is the fantastic working relationship that we’ve had over the years. ... I consider Sergio my mentor, but also a good friend and colleague. And so I think it’s this ability that we’ve had to work together and that relationship of trust, which has been key.”
“Sergio is somebody who lifts people up,” Dr. Perales added. “Many people will tell you that Sergio has helped them in their career. ... And I think that’s a lesson I’ve learned from him: training the next generation. And [that’s] not just in the U.S., but outside. I think that’s a key role that we have. And our responsibility.”
Asked to comment on their 100th-paper milestone, Dr. Perales firmly turned the spotlight from himself and Dr. Giralt to the junior investigators who have passed through the doors of the bone-marrow transplant program: “This body of work represents not just our collaboration but also the many contributions of our team at MSK ... and beyond MSK.”
This article was updated 1/26/22.
On July 29, 2021, Sergio Giralt, MD, deputy division head of the division of hematologic malignancies and Miguel-Angel Perales, MD, chief of the adult bone marrow transplant service at MSKCC, published their 100th peer-reviewed paper as coauthors. Listing hundreds of such articles on a CV is standard for top-tier physicians, but the pair had gone one better: 100 publications written together in 10 years.
Their centenary article hit scientific newsstands almost exactly a decade after their first joint paper, which appeared in September 2011, not long after they met.
Born in Cuba, Dr. Giralt grew up in Venezuela. From the age of 14, he knew that medicine was his path, and in 1984 he earned a medical degree from the Universidad Central de Venezuela, Caracas. Next came a research position at Harvard Medical School, a residency at the Good Samaritan Hospital, Cincinnati, and a fellowship at the University of Texas MD Anderson Cancer Center, Houston. Dr. Giralt arrived at MSKCC in 2010 as the new chief of the adult bone marrow transplant service. There he was introduced to a new colleague, Dr. Perales. They soon learned that in addition to expertise in hematology, they had second language in common: Spanish.
Dr. Giralt said: “We both have a Spanish background and in a certain sense, there was an affinity there. ... We both have shared experiences.”
Dr. Perales was brought up in Belgium, a European nation with three official languages: French, Dutch, and German. He speaks five tongues in all and learned Spanish from his father, who came from Spain.
Fluency in Spanish enables both physicians to take care of the many New Yorkers who are more comfortable in that language – especially when navigating cancer treatment. However, both Dr. Giralt and Dr. Perales said that a second language is more than a professional tool. They described the enjoyable change of persona that happens when they switch to Spanish.
“People who are multilingual have different roles [as much as] different languages,” said Dr. Perales. “When I’m in Spanish, part of my brain is [thinking back to] summer vacations and hanging out with my cousins.”
When it comes to clinical science, however, English is the language of choice.
Global leaders in HSCT
Dr. Giralt and Dr. Perales are known worldwide in the field of allogeneic HSCT, a potentially curative treatment for an elongating list of both malignant and nonmalignant diseases.
In 1973, MSKCC conducted the first bone-marrow transplant from an unrelated donor. Fifty years on, medical oncologists in the United States conduct approximately 8,500 allogeneic transplants each year, 72% to treat acute leukemias or myelodysplastic syndrome (MDS).
However, stripping the immune system with intensive chemotherapy ‘conditioning,’ then rebuilding it with non-diseased donor hematopoietic cells is a hazardous undertaking. Older patients are less likely to survive the intensive conditioning, so historically have missed out. Also, even with a good human leukocyte antigen (HLA) match, the recipient needs often brutal immunosuppression.
Since Dr. Giralt and Dr. Perales began their partnership in 2010, the goals of their work have not changed: to develop safer, lower-intensity transplantation suitable for older, more vulnerable patients and reduce fearsome posttransplant sequelae such as graft-versus-host disease (GVHD).
Dr. Giralt’s publication list spans more than 600 peer-reviewed papers, articles and book chapters, almost exclusively on HSCT. Dr. Perales has more than 300 publication credits on the topic.
The two paired up on their first paper just months after Dr. Giralt arrived at MSKCC. That article, published in Biology of Blood and Marrow Transplantation, compared umbilical cord blood for HSCT with donor blood in 367 people with a variety of hematologic malignancies, including acute and chronic leukemias, MDS, and lymphoma.
The MSKCC team found that transplant-related mortality in the first 180 days was higher for the cord blood (21%), but thereafter mortality and relapse were much lower than for donated blood, with the result that 2-year progression-free survival of 55% was similar. Dr. Perales, Dr. Giralt and their coauthors concluded that the data provided “strong support” for further work on cord blood as an alternative stem-cell source.
During their first decade of collaboration, Dr. Giralt and Dr. Perales worked on any promising avenue that could improve outcomes and the experience of HSCT recipients, including reduced-intensity conditioning regimens to allow older adults to benefit from curative HSCT and donor T-cell depletion by CD34 selection, to reduce graft-versus-host disease (GVHD).
The CD34 protein is typically found on the surface of early stage and highly active stem cell types. Selecting these cell types using a range of techniques can eliminate many other potentially interfering or inactive cells. This enriches the transplant population with the most effective cells and can lower the risk of GVHD.
The 100th paper on which Dr. Giralt and Dr. Perales were coauthors was published in Blood Advances on July 27, 2021. The retrospective study examined the fate of 58 MSKCC patients with a rare form of chronic lymphocytic leukemia, CLL with Richter’s transformation (CLL-RT). It was the largest such study to date of this rare disease.
M.D. Anderson Cancer Center had shown in 2006 that, despite chemotherapy, overall survival in patients with CLL-RT was approximately 8 months. HSCT improved survival dramatically (75% at 3 years; n = 7). However, with the advent of novel targeted drugs for CLL such as ibrutinib (Imbruvica), venetoclax (Venclexta), or idelalisib (Zydelig), the MSKCC team asked themselves: What was the role of reduced-intensive conditioning HSCT? Was it even safe? Among other findings, Dr. Giralt and Dr. Perales’ 100th paper showed that reduced-intensity HSCT remained a viable alternative after a CLL-RT patient progressed on a novel agent.
Impact of the pandemic
When COVID-19 hit, the team lost many research staff and developed a huge backlog, said Dr. Giralt. He and Dr. Perales realized that they needed to be “thoughtful and careful” about which studies to continue. “For example, the CD-34 selection trials we did not close because these are our workhorse trials,” Dr. Giralt said. “We have people we need to treat, and some of the patients that we need to treat can only be treated on trial.”
The team was also able to pivot some of their work into COVID 19 itself, and they collected crucial information on HSCT in recovered COVID-19 patients, as an example.
“We were living through a critical time, but that doesn’t mean we [aren’t] obligated to continue our mission, our research mission,” said Dr. Giralt. “It really is team science. The way we look at it ... there’s a common thread: We both like to do allogeneic transplant, and we both believe in trying to make CD-34 selection better. So we’re both very much [working on] how can we improve what we call ‘the Memorial way’ of doing transplants. Where we separate is, Miguel does primarily lymphoma. He doesn’t do myeloma [like me]. So in those two areas, we’re helping develop the junior faculty in a different way.”
Something more in common
Right from the start, Dr. Perales and Dr. Giralt also shared a commitment to mentoring. Since 2010, Dr. Perales has mentored 22 up-and-coming junior faculty, including 10 from Europe (8 from Spain) and 2 from Latin America.
“[It makes] the research enterprise much more productive but [these young scientists] really increase the visibility of the program,” said Dr. Giralt.
He cited Dr. Perales’ track record of mentoring as one of the reasons for his promotion to chief of the adult bone marrow transplant service. In March 2020, Dr. Perales seamlessly stepped into Dr. Giralt’s shoes, while Dr. Giralt moved on to his present role as deputy division head of the division of hematologic malignancies.
Dr. Perales said: “The key aspect [of these promotions] is the fantastic working relationship that we’ve had over the years. ... I consider Sergio my mentor, but also a good friend and colleague. And so I think it’s this ability that we’ve had to work together and that relationship of trust, which has been key.”
“Sergio is somebody who lifts people up,” Dr. Perales added. “Many people will tell you that Sergio has helped them in their career. ... And I think that’s a lesson I’ve learned from him: training the next generation. And [that’s] not just in the U.S., but outside. I think that’s a key role that we have. And our responsibility.”
Asked to comment on their 100th-paper milestone, Dr. Perales firmly turned the spotlight from himself and Dr. Giralt to the junior investigators who have passed through the doors of the bone-marrow transplant program: “This body of work represents not just our collaboration but also the many contributions of our team at MSK ... and beyond MSK.”
This article was updated 1/26/22.
Rituximab and COVID-19 vaccines: Studies begin to answer key questions
Rituximab has presented something of a conundrum for patients taking the monoclonal antibody during the COVID-19 pandemic.
Used to manage a variety of autoimmune diseases and cancers, rituximab acts against CD20 proteins expressed on the surface of B cells, causing B-cell depletion. However, it is this B-cell depletion that may put these patients at greater risk of COVID-19 development, progression to more severe disease, and in-hospital mortality. Evidence for this appears to be mixed, with studies showing both that patients using rituximab to manage various diseases are and are not at increased risk for SARS-CoV-2 infection, COVID-19 progression, and mortality.
As COVID-19 vaccine rollouts take place across the world, more questions have been raised about the relationship between B-cell depletion from anti-CD20 therapies and COVID-19 vaccines. Do rituximab and other anti-CD20 therapies affect a patient’s response to COVID-19 vaccines? If this is the case, does the timing of anti-CD20 treatment matter to maximize B-cell levels and improve the vaccine’s effectiveness? And how do COVID-19 vaccine booster doses factor into the equation?
Humoral and cell-mediated responses following COVID-19 vaccination
First, the bad news: The vaccine is unquestionably safe to administer in patients taking rituximab, but one thing that has been well established is that antibody response to COVID-19 vaccination in these individuals does is reduced. This isn’t entirely unprecedented, as previous studies have shown a weakened immune response to pneumococcal polysaccharide and keyhole limpet hemocyanin vaccines among patients taking rituximab.
“Compromised immunogenicity to the SARS-CoV-2 vaccines has been demonstrated in rituximab-treated patients, which is of particular concern given the observation that B-cell–depleting therapies may be associated with worse COVID outcomes,” Robert F. Spiera, MD, director of the Scleroderma, Vasculitis, and Myositis Center at the Hospital for Special Surgery in New York, said in an interview.
For example, in a recent study from the Medical University of Vienna, 29 (39%) of 74 patients receiving rituximab (43% as monotherapy, 57% with conventional-synthetic disease-modifying antirheumatic drugs) who were vaccinated with either the Comirnaty (Pfizer-BioNTech) or Spikevax (Moderna) COVID-19 vaccine achieved seroconversion, compared with 100% of patients in a healthy control group, and all but 1 patient without detectable CD19+ peripheral B cells did not develop anti–SARS-CoV-2 receptor-binding domain antibodies.
“There is an increasing number of studies in this field, and they confirm that patients treated with rituximab and other anti-CD20 agents have severely reduced serological responses to COVID-19 vaccines,” Ingrid Jyssum, MD, of the division of rheumatology and research at Diakonhjemmet Hospital in Oslo, said in an interview.
One silver lining is that patients treated with anti-CD20 therapies appear to have a cell-mediated response following vaccination even if they don’t develop SARS-CoV-2 antibodies. “Studies that also investigate T-cell responses are starting to emerge, and so far, they show that, even if the patients do not have antibodies, they may have T-cell responses,” Dr. Jyssum said.
One study of 24 patients with autoimmune diseases taking rituximab that evaluated humoral and T-cell responses following vaccination with the Comirnaty vaccine found that none had a humoral response to the vaccine, but the T-cell response from that group did not significantly differ from 35 patients receiving other immunosuppressants and 26 patients in a healthy control group. In another study of rituximab- or ocrelizumab-treated patients who received mRNA-based COVID-19 vaccines, 69.4% developed SARS-CoV-2–specific antibodies, compared with a control group, but 96.2% of patients taking ocrelizumab and 81.8% of patients taking rituximab mounted a spike-specific CD8+ T-cell response, compared with 66.7% in the control group, and there were comparable rates (85%-90%) of spike-specific CD4+ T cells in all groups. In the study from the Medical University of Vienna, T-cell response was detected in rituximab-treated patients who both did and did not mount an antibody response.
The clinical relevance of how a blunted humoral immune response but a respectable T-cell response to COVID-19 vaccines affects patients treated with anti-CD20 therapies isn’t currently known, Dr. Jyssum said.
While these data are reassuring, they’re also incomplete, Dr. Spiera noted. “The ultimate outcome of relevance to assess vaccine efficacy is protection from COVID and from severe outcomes of COVID infection (i.e., hospitalization, mechanical ventilation, death). That data will require assessment of very large numbers of rituximab-treated vaccinated patients to be compared with rituximab-treated unvaccinated patients, and is unlikely to be forthcoming in the very near future.
“In the meantime, however, achieving serologic positivity, meaning having evidence of serologic as well as cellular immunity following vaccination, is a desired outcome, and likely implies more robust immunity.”
Does treatment timing impact COVID-19 vaccine response?
Given enough time, B-cell reconstitution will occur in patients taking rituximab. With that in mind, is it beneficial to wait a certain amount of time after a patient has stopped rituximab therapy or time since their last dose before giving them a COVID-19 vaccine? In their guidance on COVID-19 vaccines for patients with rheumatic and musculoskeletal diseases, the American College of Rheumatology said there is moderate evidence to consider “optimal timing of dosing and vaccination with the rheumatology provider before proceeding.”
“Guidelines and preliminary studies of serologic response to COVID vaccine in rituximab-treated patients have suggested that longer time from last rituximab exposure is associated with a greater likelihood of a serologic response,” Dr. Spiera said.
In a brief report published in Arthritis & Rheumatology, Dr. Spiera and colleagues performed a retrospective chart review of 56 patients with varying levels of last exposure to rituximab who received a COVID-19 vaccine. Their results showed that, when patients were vaccinated 6-12 months after the last rituximab dose, 55% were seronegative, and when this was more than 12 months, only 13% were seronegative, compared with seronegativity in 86% who were vaccinated less than 6 months after their last rituximab dose.
The RituxiVac trial, conducted by researchers in Switzerland, also examined vaccine responses of 96 rituximab-treated patients who received Comirnaty or Spikevax; results recently published in The Lancet Rheumatology showed findings similar to other studies, with reduced humoral and cell-mediated responses. In the RituxiVac trial, the median time to last anti-CD20 treatment was 1.07 years.
“The typical interval between rituximab doses [for treatment of rheumatoid arthritis, as well as for remission maintenance in antineutrophil cytoplasmic antibody–associated vasculitis] is typically 6 months, and this has become widely used as the interval from last rituximab to time of COVID vaccination, with a recommendation to wait 4 weeks (if possible) from time of vaccination until the next rituximab administration,” Dr. Spiera explained. However, this window seems to vary depending on the study.
Recent research published in Arthritis & Rheumatology indicates B-cell levels could be a relevant indicator for humoral and cell-mediated response in patients with rheumatic diseases treated with rituximab, with a level of 10 B cells/mcL (0.4% of lymphocytes) identified as one potential marker for likely seroconversion following COVID-19 vaccination.
“In some smaller case series, it has been further recognized that rituximab-treated patients who were beginning to reconstitute peripheral B cells were most likely to respond serologically. Our present study confirmed those findings, demonstrating that the presence of detectable B cells was strongly associated with vaccine responsiveness, and affords complementary information to time from last [rituximab dose] in informing the likelihood of a vaccine response,” Dr. Spiera said.
However, the literature is limited in this area, and an exact cutoff for B-cell counts in these patients isn’t currently known, Dr. Jyssum said. A better metric is time away from anti-CD20 therapies, with CD19 cell count being highly correlated with last infusion.
Dr. Spiera agreed that there is no consistent B-cell percentage that works as a cutoff. “In our study, we looked at it as a binary variable, although we did find that a higher percentage of B cells in the peripheral lymphocyte population was associated with a higher likelihood of seroconversion. We did not, however, identify a ‘threshold’ for vaccine serologic responsiveness.”
Should clinicians measure antibodies?
The Food and Drug Administration and the Centers for Disease Control and Prevention have recommended that health care providers and the public not use COVID-19 antibody tests as a way to gauge immunity after exposure to SARS-CoV-2 and after receiving a COVID-19 vaccination. The ACR’s guidance on COVID-19 vaccination for patients with rheumatic and musculoskeletal diseases strongly recommends against ordering antibody tests for patients with autoimmune inflammatory rheumatic diseases as a way to measure immunity.
“Generally, such measurements are not recommended as the clinical correlate of various antibody levels are not known,” Dr. Jyssum said. “With regular infusions of rituximab or other anti-CD20 agents, one cannot expect that these patients will develop significant levels of antibodies.”
However, she said there might be situations where it’s useful to know whether a patient has developed antibodies at all. “Assessing the significance of specific antibody levels is difficult, and the subject of scientific studies. Patients lacking a humoral vaccine response are left to rely on their T-cell responses and on infectious control measures to prevent disease.”
Dr. Spiera said he disagreed with guidelines recommending against checking antibody levels after vaccination, “particularly in patients treated with immunosuppressive medications that might be expected to blunt their serologic response to the vaccines.
“Although we cannot be sure what level of measurable antibodies offer what level of protection, most clinicians would agree that patients who demonstrate no detectable antibodies (which is a common finding in rituximab-treated patients) should be considered at higher risk,” he said. “Indeed, recommendations regarding booster vaccine administration in general was initially based on the observation of declining antibody levels with longer time from vaccination.”
Do COVID-19 vaccine boosters help patients on anti-CD20 therapy?
As of January 2022, the FDA and CDC have recommended a third primary series shot of COVID-19 vaccines for some moderately to severely immunocompromised patients as young as 5 years old (for Comirnaty vaccine) or a booster shot of either Comirnaty or Spikevax for everyone aged 12 years and older, including immunocompromised people, while the ACR goes into more detail and recommends clinicians time a patient’s booster shot with temporary treatment interruption.
In The Lancet Rheumatology, Dr. Jyssum and colleagues recently published results from the prospective Nor-vaC study examining the humoral and cell-mediated immune responses of 87 patients with RA being treated with rituximab who received the Comirnaty, Spikevax, or Vaxzevria (AstraZeneca) COVID-19 vaccines; of these, 49 patients received a booster dose at a median of 70 days after completing their primary series. The results showed 19 patients (28.1%) had a serologic response after their primary series, while 8 of 49 patients (16.3%) who received their booster dose had a serologic response.
All patients who received a third dose in the study had a T-cell response, Dr. Jyssum said. “This is reassuring for patients and clinicians. T cells have been found to be important in countering COVID-19 disease, but whether we can rely on the T-cell response alone in the absence of antibodies to protect patients from infection or from serious COVID disease is still not determined,” she said.
When asked if she would recommend COVID-19 vaccine booster doses for patients on rituximab, Dr. Jyssum replied: “Absolutely.”
Another study, recently published in Annals of the Rheumatic Diseases, examined heterologous and homologous booster doses for 60 patients receiving rituximab without seroconversion after their COVID-19 vaccine primary series. The results showed no significant difference in new seroconversion at 4 weeks based on whether the patient received a vector or mRNA vaccine (22% vs. 32%), but all patients who received a booster dose with a vector vaccine had specific T-cell responses, compared with 81% of patients who received an mRNA vaccine booster. There was a new humoral and/or cellular response in 9 of 11 patients (82%), and most patients with peripheral B cells (12 of 18 patients; 67%) achieved seroconversion.
“Our data show that a cellular and/or humoral immune response can be achieved on a third COVID-19 vaccination in most of the patients who initially developed neither a humoral nor a cellular immune response,” the researchers concluded. “The efficacy data together with the safety data seen in our trial provide a favorable risk/benefit ratio and support the implementation of a third vaccination for nonseroconverted high-risk autoimmune disease patients treated with B-cell–depleting agents.”
Dr. Spiera said booster doses are an important part of the equation, and “it is important to consider factors that would be associated with a greater likelihood of achieving a serologic response, particularly in those patients who did not demonstrate a serologic response to the initial vaccines series.
“Preliminary data shows that the beginnings of B-cell reconstitution is also associated with a positive serologic response following a booster of the COVID-19 vaccine,” he said.
The authors of the cited studies reported numerous relevant financial disclosures. Dr. Spiera and Dr. Jyssum reported no relevant financial disclosures.
Rituximab has presented something of a conundrum for patients taking the monoclonal antibody during the COVID-19 pandemic.
Used to manage a variety of autoimmune diseases and cancers, rituximab acts against CD20 proteins expressed on the surface of B cells, causing B-cell depletion. However, it is this B-cell depletion that may put these patients at greater risk of COVID-19 development, progression to more severe disease, and in-hospital mortality. Evidence for this appears to be mixed, with studies showing both that patients using rituximab to manage various diseases are and are not at increased risk for SARS-CoV-2 infection, COVID-19 progression, and mortality.
As COVID-19 vaccine rollouts take place across the world, more questions have been raised about the relationship between B-cell depletion from anti-CD20 therapies and COVID-19 vaccines. Do rituximab and other anti-CD20 therapies affect a patient’s response to COVID-19 vaccines? If this is the case, does the timing of anti-CD20 treatment matter to maximize B-cell levels and improve the vaccine’s effectiveness? And how do COVID-19 vaccine booster doses factor into the equation?
Humoral and cell-mediated responses following COVID-19 vaccination
First, the bad news: The vaccine is unquestionably safe to administer in patients taking rituximab, but one thing that has been well established is that antibody response to COVID-19 vaccination in these individuals does is reduced. This isn’t entirely unprecedented, as previous studies have shown a weakened immune response to pneumococcal polysaccharide and keyhole limpet hemocyanin vaccines among patients taking rituximab.
“Compromised immunogenicity to the SARS-CoV-2 vaccines has been demonstrated in rituximab-treated patients, which is of particular concern given the observation that B-cell–depleting therapies may be associated with worse COVID outcomes,” Robert F. Spiera, MD, director of the Scleroderma, Vasculitis, and Myositis Center at the Hospital for Special Surgery in New York, said in an interview.
For example, in a recent study from the Medical University of Vienna, 29 (39%) of 74 patients receiving rituximab (43% as monotherapy, 57% with conventional-synthetic disease-modifying antirheumatic drugs) who were vaccinated with either the Comirnaty (Pfizer-BioNTech) or Spikevax (Moderna) COVID-19 vaccine achieved seroconversion, compared with 100% of patients in a healthy control group, and all but 1 patient without detectable CD19+ peripheral B cells did not develop anti–SARS-CoV-2 receptor-binding domain antibodies.
“There is an increasing number of studies in this field, and they confirm that patients treated with rituximab and other anti-CD20 agents have severely reduced serological responses to COVID-19 vaccines,” Ingrid Jyssum, MD, of the division of rheumatology and research at Diakonhjemmet Hospital in Oslo, said in an interview.
One silver lining is that patients treated with anti-CD20 therapies appear to have a cell-mediated response following vaccination even if they don’t develop SARS-CoV-2 antibodies. “Studies that also investigate T-cell responses are starting to emerge, and so far, they show that, even if the patients do not have antibodies, they may have T-cell responses,” Dr. Jyssum said.
One study of 24 patients with autoimmune diseases taking rituximab that evaluated humoral and T-cell responses following vaccination with the Comirnaty vaccine found that none had a humoral response to the vaccine, but the T-cell response from that group did not significantly differ from 35 patients receiving other immunosuppressants and 26 patients in a healthy control group. In another study of rituximab- or ocrelizumab-treated patients who received mRNA-based COVID-19 vaccines, 69.4% developed SARS-CoV-2–specific antibodies, compared with a control group, but 96.2% of patients taking ocrelizumab and 81.8% of patients taking rituximab mounted a spike-specific CD8+ T-cell response, compared with 66.7% in the control group, and there were comparable rates (85%-90%) of spike-specific CD4+ T cells in all groups. In the study from the Medical University of Vienna, T-cell response was detected in rituximab-treated patients who both did and did not mount an antibody response.
The clinical relevance of how a blunted humoral immune response but a respectable T-cell response to COVID-19 vaccines affects patients treated with anti-CD20 therapies isn’t currently known, Dr. Jyssum said.
While these data are reassuring, they’re also incomplete, Dr. Spiera noted. “The ultimate outcome of relevance to assess vaccine efficacy is protection from COVID and from severe outcomes of COVID infection (i.e., hospitalization, mechanical ventilation, death). That data will require assessment of very large numbers of rituximab-treated vaccinated patients to be compared with rituximab-treated unvaccinated patients, and is unlikely to be forthcoming in the very near future.
“In the meantime, however, achieving serologic positivity, meaning having evidence of serologic as well as cellular immunity following vaccination, is a desired outcome, and likely implies more robust immunity.”
Does treatment timing impact COVID-19 vaccine response?
Given enough time, B-cell reconstitution will occur in patients taking rituximab. With that in mind, is it beneficial to wait a certain amount of time after a patient has stopped rituximab therapy or time since their last dose before giving them a COVID-19 vaccine? In their guidance on COVID-19 vaccines for patients with rheumatic and musculoskeletal diseases, the American College of Rheumatology said there is moderate evidence to consider “optimal timing of dosing and vaccination with the rheumatology provider before proceeding.”
“Guidelines and preliminary studies of serologic response to COVID vaccine in rituximab-treated patients have suggested that longer time from last rituximab exposure is associated with a greater likelihood of a serologic response,” Dr. Spiera said.
In a brief report published in Arthritis & Rheumatology, Dr. Spiera and colleagues performed a retrospective chart review of 56 patients with varying levels of last exposure to rituximab who received a COVID-19 vaccine. Their results showed that, when patients were vaccinated 6-12 months after the last rituximab dose, 55% were seronegative, and when this was more than 12 months, only 13% were seronegative, compared with seronegativity in 86% who were vaccinated less than 6 months after their last rituximab dose.
The RituxiVac trial, conducted by researchers in Switzerland, also examined vaccine responses of 96 rituximab-treated patients who received Comirnaty or Spikevax; results recently published in The Lancet Rheumatology showed findings similar to other studies, with reduced humoral and cell-mediated responses. In the RituxiVac trial, the median time to last anti-CD20 treatment was 1.07 years.
“The typical interval between rituximab doses [for treatment of rheumatoid arthritis, as well as for remission maintenance in antineutrophil cytoplasmic antibody–associated vasculitis] is typically 6 months, and this has become widely used as the interval from last rituximab to time of COVID vaccination, with a recommendation to wait 4 weeks (if possible) from time of vaccination until the next rituximab administration,” Dr. Spiera explained. However, this window seems to vary depending on the study.
Recent research published in Arthritis & Rheumatology indicates B-cell levels could be a relevant indicator for humoral and cell-mediated response in patients with rheumatic diseases treated with rituximab, with a level of 10 B cells/mcL (0.4% of lymphocytes) identified as one potential marker for likely seroconversion following COVID-19 vaccination.
“In some smaller case series, it has been further recognized that rituximab-treated patients who were beginning to reconstitute peripheral B cells were most likely to respond serologically. Our present study confirmed those findings, demonstrating that the presence of detectable B cells was strongly associated with vaccine responsiveness, and affords complementary information to time from last [rituximab dose] in informing the likelihood of a vaccine response,” Dr. Spiera said.
However, the literature is limited in this area, and an exact cutoff for B-cell counts in these patients isn’t currently known, Dr. Jyssum said. A better metric is time away from anti-CD20 therapies, with CD19 cell count being highly correlated with last infusion.
Dr. Spiera agreed that there is no consistent B-cell percentage that works as a cutoff. “In our study, we looked at it as a binary variable, although we did find that a higher percentage of B cells in the peripheral lymphocyte population was associated with a higher likelihood of seroconversion. We did not, however, identify a ‘threshold’ for vaccine serologic responsiveness.”
Should clinicians measure antibodies?
The Food and Drug Administration and the Centers for Disease Control and Prevention have recommended that health care providers and the public not use COVID-19 antibody tests as a way to gauge immunity after exposure to SARS-CoV-2 and after receiving a COVID-19 vaccination. The ACR’s guidance on COVID-19 vaccination for patients with rheumatic and musculoskeletal diseases strongly recommends against ordering antibody tests for patients with autoimmune inflammatory rheumatic diseases as a way to measure immunity.
“Generally, such measurements are not recommended as the clinical correlate of various antibody levels are not known,” Dr. Jyssum said. “With regular infusions of rituximab or other anti-CD20 agents, one cannot expect that these patients will develop significant levels of antibodies.”
However, she said there might be situations where it’s useful to know whether a patient has developed antibodies at all. “Assessing the significance of specific antibody levels is difficult, and the subject of scientific studies. Patients lacking a humoral vaccine response are left to rely on their T-cell responses and on infectious control measures to prevent disease.”
Dr. Spiera said he disagreed with guidelines recommending against checking antibody levels after vaccination, “particularly in patients treated with immunosuppressive medications that might be expected to blunt their serologic response to the vaccines.
“Although we cannot be sure what level of measurable antibodies offer what level of protection, most clinicians would agree that patients who demonstrate no detectable antibodies (which is a common finding in rituximab-treated patients) should be considered at higher risk,” he said. “Indeed, recommendations regarding booster vaccine administration in general was initially based on the observation of declining antibody levels with longer time from vaccination.”
Do COVID-19 vaccine boosters help patients on anti-CD20 therapy?
As of January 2022, the FDA and CDC have recommended a third primary series shot of COVID-19 vaccines for some moderately to severely immunocompromised patients as young as 5 years old (for Comirnaty vaccine) or a booster shot of either Comirnaty or Spikevax for everyone aged 12 years and older, including immunocompromised people, while the ACR goes into more detail and recommends clinicians time a patient’s booster shot with temporary treatment interruption.
In The Lancet Rheumatology, Dr. Jyssum and colleagues recently published results from the prospective Nor-vaC study examining the humoral and cell-mediated immune responses of 87 patients with RA being treated with rituximab who received the Comirnaty, Spikevax, or Vaxzevria (AstraZeneca) COVID-19 vaccines; of these, 49 patients received a booster dose at a median of 70 days after completing their primary series. The results showed 19 patients (28.1%) had a serologic response after their primary series, while 8 of 49 patients (16.3%) who received their booster dose had a serologic response.
All patients who received a third dose in the study had a T-cell response, Dr. Jyssum said. “This is reassuring for patients and clinicians. T cells have been found to be important in countering COVID-19 disease, but whether we can rely on the T-cell response alone in the absence of antibodies to protect patients from infection or from serious COVID disease is still not determined,” she said.
When asked if she would recommend COVID-19 vaccine booster doses for patients on rituximab, Dr. Jyssum replied: “Absolutely.”
Another study, recently published in Annals of the Rheumatic Diseases, examined heterologous and homologous booster doses for 60 patients receiving rituximab without seroconversion after their COVID-19 vaccine primary series. The results showed no significant difference in new seroconversion at 4 weeks based on whether the patient received a vector or mRNA vaccine (22% vs. 32%), but all patients who received a booster dose with a vector vaccine had specific T-cell responses, compared with 81% of patients who received an mRNA vaccine booster. There was a new humoral and/or cellular response in 9 of 11 patients (82%), and most patients with peripheral B cells (12 of 18 patients; 67%) achieved seroconversion.
“Our data show that a cellular and/or humoral immune response can be achieved on a third COVID-19 vaccination in most of the patients who initially developed neither a humoral nor a cellular immune response,” the researchers concluded. “The efficacy data together with the safety data seen in our trial provide a favorable risk/benefit ratio and support the implementation of a third vaccination for nonseroconverted high-risk autoimmune disease patients treated with B-cell–depleting agents.”
Dr. Spiera said booster doses are an important part of the equation, and “it is important to consider factors that would be associated with a greater likelihood of achieving a serologic response, particularly in those patients who did not demonstrate a serologic response to the initial vaccines series.
“Preliminary data shows that the beginnings of B-cell reconstitution is also associated with a positive serologic response following a booster of the COVID-19 vaccine,” he said.
The authors of the cited studies reported numerous relevant financial disclosures. Dr. Spiera and Dr. Jyssum reported no relevant financial disclosures.
Rituximab has presented something of a conundrum for patients taking the monoclonal antibody during the COVID-19 pandemic.
Used to manage a variety of autoimmune diseases and cancers, rituximab acts against CD20 proteins expressed on the surface of B cells, causing B-cell depletion. However, it is this B-cell depletion that may put these patients at greater risk of COVID-19 development, progression to more severe disease, and in-hospital mortality. Evidence for this appears to be mixed, with studies showing both that patients using rituximab to manage various diseases are and are not at increased risk for SARS-CoV-2 infection, COVID-19 progression, and mortality.
As COVID-19 vaccine rollouts take place across the world, more questions have been raised about the relationship between B-cell depletion from anti-CD20 therapies and COVID-19 vaccines. Do rituximab and other anti-CD20 therapies affect a patient’s response to COVID-19 vaccines? If this is the case, does the timing of anti-CD20 treatment matter to maximize B-cell levels and improve the vaccine’s effectiveness? And how do COVID-19 vaccine booster doses factor into the equation?
Humoral and cell-mediated responses following COVID-19 vaccination
First, the bad news: The vaccine is unquestionably safe to administer in patients taking rituximab, but one thing that has been well established is that antibody response to COVID-19 vaccination in these individuals does is reduced. This isn’t entirely unprecedented, as previous studies have shown a weakened immune response to pneumococcal polysaccharide and keyhole limpet hemocyanin vaccines among patients taking rituximab.
“Compromised immunogenicity to the SARS-CoV-2 vaccines has been demonstrated in rituximab-treated patients, which is of particular concern given the observation that B-cell–depleting therapies may be associated with worse COVID outcomes,” Robert F. Spiera, MD, director of the Scleroderma, Vasculitis, and Myositis Center at the Hospital for Special Surgery in New York, said in an interview.
For example, in a recent study from the Medical University of Vienna, 29 (39%) of 74 patients receiving rituximab (43% as monotherapy, 57% with conventional-synthetic disease-modifying antirheumatic drugs) who were vaccinated with either the Comirnaty (Pfizer-BioNTech) or Spikevax (Moderna) COVID-19 vaccine achieved seroconversion, compared with 100% of patients in a healthy control group, and all but 1 patient without detectable CD19+ peripheral B cells did not develop anti–SARS-CoV-2 receptor-binding domain antibodies.
“There is an increasing number of studies in this field, and they confirm that patients treated with rituximab and other anti-CD20 agents have severely reduced serological responses to COVID-19 vaccines,” Ingrid Jyssum, MD, of the division of rheumatology and research at Diakonhjemmet Hospital in Oslo, said in an interview.
One silver lining is that patients treated with anti-CD20 therapies appear to have a cell-mediated response following vaccination even if they don’t develop SARS-CoV-2 antibodies. “Studies that also investigate T-cell responses are starting to emerge, and so far, they show that, even if the patients do not have antibodies, they may have T-cell responses,” Dr. Jyssum said.
One study of 24 patients with autoimmune diseases taking rituximab that evaluated humoral and T-cell responses following vaccination with the Comirnaty vaccine found that none had a humoral response to the vaccine, but the T-cell response from that group did not significantly differ from 35 patients receiving other immunosuppressants and 26 patients in a healthy control group. In another study of rituximab- or ocrelizumab-treated patients who received mRNA-based COVID-19 vaccines, 69.4% developed SARS-CoV-2–specific antibodies, compared with a control group, but 96.2% of patients taking ocrelizumab and 81.8% of patients taking rituximab mounted a spike-specific CD8+ T-cell response, compared with 66.7% in the control group, and there were comparable rates (85%-90%) of spike-specific CD4+ T cells in all groups. In the study from the Medical University of Vienna, T-cell response was detected in rituximab-treated patients who both did and did not mount an antibody response.
The clinical relevance of how a blunted humoral immune response but a respectable T-cell response to COVID-19 vaccines affects patients treated with anti-CD20 therapies isn’t currently known, Dr. Jyssum said.
While these data are reassuring, they’re also incomplete, Dr. Spiera noted. “The ultimate outcome of relevance to assess vaccine efficacy is protection from COVID and from severe outcomes of COVID infection (i.e., hospitalization, mechanical ventilation, death). That data will require assessment of very large numbers of rituximab-treated vaccinated patients to be compared with rituximab-treated unvaccinated patients, and is unlikely to be forthcoming in the very near future.
“In the meantime, however, achieving serologic positivity, meaning having evidence of serologic as well as cellular immunity following vaccination, is a desired outcome, and likely implies more robust immunity.”
Does treatment timing impact COVID-19 vaccine response?
Given enough time, B-cell reconstitution will occur in patients taking rituximab. With that in mind, is it beneficial to wait a certain amount of time after a patient has stopped rituximab therapy or time since their last dose before giving them a COVID-19 vaccine? In their guidance on COVID-19 vaccines for patients with rheumatic and musculoskeletal diseases, the American College of Rheumatology said there is moderate evidence to consider “optimal timing of dosing and vaccination with the rheumatology provider before proceeding.”
“Guidelines and preliminary studies of serologic response to COVID vaccine in rituximab-treated patients have suggested that longer time from last rituximab exposure is associated with a greater likelihood of a serologic response,” Dr. Spiera said.
In a brief report published in Arthritis & Rheumatology, Dr. Spiera and colleagues performed a retrospective chart review of 56 patients with varying levels of last exposure to rituximab who received a COVID-19 vaccine. Their results showed that, when patients were vaccinated 6-12 months after the last rituximab dose, 55% were seronegative, and when this was more than 12 months, only 13% were seronegative, compared with seronegativity in 86% who were vaccinated less than 6 months after their last rituximab dose.
The RituxiVac trial, conducted by researchers in Switzerland, also examined vaccine responses of 96 rituximab-treated patients who received Comirnaty or Spikevax; results recently published in The Lancet Rheumatology showed findings similar to other studies, with reduced humoral and cell-mediated responses. In the RituxiVac trial, the median time to last anti-CD20 treatment was 1.07 years.
“The typical interval between rituximab doses [for treatment of rheumatoid arthritis, as well as for remission maintenance in antineutrophil cytoplasmic antibody–associated vasculitis] is typically 6 months, and this has become widely used as the interval from last rituximab to time of COVID vaccination, with a recommendation to wait 4 weeks (if possible) from time of vaccination until the next rituximab administration,” Dr. Spiera explained. However, this window seems to vary depending on the study.
Recent research published in Arthritis & Rheumatology indicates B-cell levels could be a relevant indicator for humoral and cell-mediated response in patients with rheumatic diseases treated with rituximab, with a level of 10 B cells/mcL (0.4% of lymphocytes) identified as one potential marker for likely seroconversion following COVID-19 vaccination.
“In some smaller case series, it has been further recognized that rituximab-treated patients who were beginning to reconstitute peripheral B cells were most likely to respond serologically. Our present study confirmed those findings, demonstrating that the presence of detectable B cells was strongly associated with vaccine responsiveness, and affords complementary information to time from last [rituximab dose] in informing the likelihood of a vaccine response,” Dr. Spiera said.
However, the literature is limited in this area, and an exact cutoff for B-cell counts in these patients isn’t currently known, Dr. Jyssum said. A better metric is time away from anti-CD20 therapies, with CD19 cell count being highly correlated with last infusion.
Dr. Spiera agreed that there is no consistent B-cell percentage that works as a cutoff. “In our study, we looked at it as a binary variable, although we did find that a higher percentage of B cells in the peripheral lymphocyte population was associated with a higher likelihood of seroconversion. We did not, however, identify a ‘threshold’ for vaccine serologic responsiveness.”
Should clinicians measure antibodies?
The Food and Drug Administration and the Centers for Disease Control and Prevention have recommended that health care providers and the public not use COVID-19 antibody tests as a way to gauge immunity after exposure to SARS-CoV-2 and after receiving a COVID-19 vaccination. The ACR’s guidance on COVID-19 vaccination for patients with rheumatic and musculoskeletal diseases strongly recommends against ordering antibody tests for patients with autoimmune inflammatory rheumatic diseases as a way to measure immunity.
“Generally, such measurements are not recommended as the clinical correlate of various antibody levels are not known,” Dr. Jyssum said. “With regular infusions of rituximab or other anti-CD20 agents, one cannot expect that these patients will develop significant levels of antibodies.”
However, she said there might be situations where it’s useful to know whether a patient has developed antibodies at all. “Assessing the significance of specific antibody levels is difficult, and the subject of scientific studies. Patients lacking a humoral vaccine response are left to rely on their T-cell responses and on infectious control measures to prevent disease.”
Dr. Spiera said he disagreed with guidelines recommending against checking antibody levels after vaccination, “particularly in patients treated with immunosuppressive medications that might be expected to blunt their serologic response to the vaccines.
“Although we cannot be sure what level of measurable antibodies offer what level of protection, most clinicians would agree that patients who demonstrate no detectable antibodies (which is a common finding in rituximab-treated patients) should be considered at higher risk,” he said. “Indeed, recommendations regarding booster vaccine administration in general was initially based on the observation of declining antibody levels with longer time from vaccination.”
Do COVID-19 vaccine boosters help patients on anti-CD20 therapy?
As of January 2022, the FDA and CDC have recommended a third primary series shot of COVID-19 vaccines for some moderately to severely immunocompromised patients as young as 5 years old (for Comirnaty vaccine) or a booster shot of either Comirnaty or Spikevax for everyone aged 12 years and older, including immunocompromised people, while the ACR goes into more detail and recommends clinicians time a patient’s booster shot with temporary treatment interruption.
In The Lancet Rheumatology, Dr. Jyssum and colleagues recently published results from the prospective Nor-vaC study examining the humoral and cell-mediated immune responses of 87 patients with RA being treated with rituximab who received the Comirnaty, Spikevax, or Vaxzevria (AstraZeneca) COVID-19 vaccines; of these, 49 patients received a booster dose at a median of 70 days after completing their primary series. The results showed 19 patients (28.1%) had a serologic response after their primary series, while 8 of 49 patients (16.3%) who received their booster dose had a serologic response.
All patients who received a third dose in the study had a T-cell response, Dr. Jyssum said. “This is reassuring for patients and clinicians. T cells have been found to be important in countering COVID-19 disease, but whether we can rely on the T-cell response alone in the absence of antibodies to protect patients from infection or from serious COVID disease is still not determined,” she said.
When asked if she would recommend COVID-19 vaccine booster doses for patients on rituximab, Dr. Jyssum replied: “Absolutely.”
Another study, recently published in Annals of the Rheumatic Diseases, examined heterologous and homologous booster doses for 60 patients receiving rituximab without seroconversion after their COVID-19 vaccine primary series. The results showed no significant difference in new seroconversion at 4 weeks based on whether the patient received a vector or mRNA vaccine (22% vs. 32%), but all patients who received a booster dose with a vector vaccine had specific T-cell responses, compared with 81% of patients who received an mRNA vaccine booster. There was a new humoral and/or cellular response in 9 of 11 patients (82%), and most patients with peripheral B cells (12 of 18 patients; 67%) achieved seroconversion.
“Our data show that a cellular and/or humoral immune response can be achieved on a third COVID-19 vaccination in most of the patients who initially developed neither a humoral nor a cellular immune response,” the researchers concluded. “The efficacy data together with the safety data seen in our trial provide a favorable risk/benefit ratio and support the implementation of a third vaccination for nonseroconverted high-risk autoimmune disease patients treated with B-cell–depleting agents.”
Dr. Spiera said booster doses are an important part of the equation, and “it is important to consider factors that would be associated with a greater likelihood of achieving a serologic response, particularly in those patients who did not demonstrate a serologic response to the initial vaccines series.
“Preliminary data shows that the beginnings of B-cell reconstitution is also associated with a positive serologic response following a booster of the COVID-19 vaccine,” he said.
The authors of the cited studies reported numerous relevant financial disclosures. Dr. Spiera and Dr. Jyssum reported no relevant financial disclosures.
‘Highly encouraging’ MRD results for zanubrutinib add-on in CLL
Treatment was stopped in the single-arm phase 2 trial when patients reached undetectable MRD, a novel use of MRD to guide treatment duration. At a median of 16 months after discontinuation, MRD remained undetectable in 31 of 33 patients (94%).
The team also found that a reduction to 1/400 of baseline MRD (delta-MRD400) by day 1 of cycle five predicted undetectable bone marrow MRD within eight treatment cycles.
delta-MRD400 is “a potential biomarker” to identify patients who’ll do well with a shorter treatment and flag others who require longer courses of therapy, said investigators led by Jacob Soumerai, MD, a hematologist/oncologist at Massachusetts General Hospital, Boston.
Overall, the results “are highly encouraging,” they said, with efficacy and safety comparing favorably to trials that added other BTK inhibitors – namely ibrutinib and acalabrutinib – to the standard obinutuzumab/venetoclax backbone, with a shorter treatment duration.
They said the novel triplet warrants further study in the first line and noted that they also “plan to prospectively validate early-MRD-response kinetics as a biomarker to guide treatment duration.” The study was published recently in The Lancet Haematology.
Two editorialists – Davide Rossi, MD, PhD, and Joyce Marques De Almeida, both of the of the Oncology Institute of Southern Switzerland, Bellinzona – were encouraged by the findings and wanted future research to assess how well MRD-guided treatment duration works in patients with tumor protein p53-disrupted disease, who “benefit less from time-limited therapies” then patients with wild-type TP53; the trial was too small to address the issue.
There was a two-cycle lead-in with zanubrutinib and obinutuzumab then venetoclax ramp-up starting at cycle 3, with each cycle running 28 days.
Zanubrutinib is approved in the U.S. for mantle cell lymphoma, Waldenström’s macroglobulinemia, and marginal zone lymphoma.
In a previous phase 2 trial of ibrutinib add-on to venetoclax-obinutuzumab for 14 cycles followed by ibrutinib monotherapy, the rate of undetectable MRD in both peripheral blood and bone marrow was 67%. The rate of bone marrow undetectable MRD was 77% in another phase 2 trial of acalabrutinib, venetoclax, and obinutuzumab for at least 15 cycles.
Dr. Soumerai and his team cautioned, however, that “comparisons across trials are fraught with selection bias resulting in differences in treated patient populations, and randomized data are needed to establish the optimal BTK inhibitor to combine with venetoclax with or without obinutuzumab, and to establish whether” the zanubrutinib triplet “improves progression-free survival and overall survival compared with current standard first-line therapy.”
There was grade 3 or worse neutropenia in 18% of subjects (7/39), one episode of febrile neutropenia (3%), lung infections in three patients (8%) patients, and five cases of hypertension (13%).
The editorialists characterized the numbers as low and the regimen as well tolerated. Past studies of ibrutinib, a first generation BTK, with venetoclax and obinutuzumab have pegged grade 3 or worse neutropenia at 56% and the hypertension incidence at 48%.
Granulocyte colony-stimulating factor administration “could partially account for the low incidence of severe neutropenia” in the trial, the investigators said.
The study was funded by zanubrutinib marketer Beigene as well as Genentech, the National Cancer Institute, and others. Many of the authors had industry ties, including Dr. Soumerai who reported being a consultant and researcher for Beigene and other companies. Dr. Rossi reported honoraria and research grants from AbbVie, AstraZeneca, and Janssen.
Treatment was stopped in the single-arm phase 2 trial when patients reached undetectable MRD, a novel use of MRD to guide treatment duration. At a median of 16 months after discontinuation, MRD remained undetectable in 31 of 33 patients (94%).
The team also found that a reduction to 1/400 of baseline MRD (delta-MRD400) by day 1 of cycle five predicted undetectable bone marrow MRD within eight treatment cycles.
delta-MRD400 is “a potential biomarker” to identify patients who’ll do well with a shorter treatment and flag others who require longer courses of therapy, said investigators led by Jacob Soumerai, MD, a hematologist/oncologist at Massachusetts General Hospital, Boston.
Overall, the results “are highly encouraging,” they said, with efficacy and safety comparing favorably to trials that added other BTK inhibitors – namely ibrutinib and acalabrutinib – to the standard obinutuzumab/venetoclax backbone, with a shorter treatment duration.
They said the novel triplet warrants further study in the first line and noted that they also “plan to prospectively validate early-MRD-response kinetics as a biomarker to guide treatment duration.” The study was published recently in The Lancet Haematology.
Two editorialists – Davide Rossi, MD, PhD, and Joyce Marques De Almeida, both of the of the Oncology Institute of Southern Switzerland, Bellinzona – were encouraged by the findings and wanted future research to assess how well MRD-guided treatment duration works in patients with tumor protein p53-disrupted disease, who “benefit less from time-limited therapies” then patients with wild-type TP53; the trial was too small to address the issue.
There was a two-cycle lead-in with zanubrutinib and obinutuzumab then venetoclax ramp-up starting at cycle 3, with each cycle running 28 days.
Zanubrutinib is approved in the U.S. for mantle cell lymphoma, Waldenström’s macroglobulinemia, and marginal zone lymphoma.
In a previous phase 2 trial of ibrutinib add-on to venetoclax-obinutuzumab for 14 cycles followed by ibrutinib monotherapy, the rate of undetectable MRD in both peripheral blood and bone marrow was 67%. The rate of bone marrow undetectable MRD was 77% in another phase 2 trial of acalabrutinib, venetoclax, and obinutuzumab for at least 15 cycles.
Dr. Soumerai and his team cautioned, however, that “comparisons across trials are fraught with selection bias resulting in differences in treated patient populations, and randomized data are needed to establish the optimal BTK inhibitor to combine with venetoclax with or without obinutuzumab, and to establish whether” the zanubrutinib triplet “improves progression-free survival and overall survival compared with current standard first-line therapy.”
There was grade 3 or worse neutropenia in 18% of subjects (7/39), one episode of febrile neutropenia (3%), lung infections in three patients (8%) patients, and five cases of hypertension (13%).
The editorialists characterized the numbers as low and the regimen as well tolerated. Past studies of ibrutinib, a first generation BTK, with venetoclax and obinutuzumab have pegged grade 3 or worse neutropenia at 56% and the hypertension incidence at 48%.
Granulocyte colony-stimulating factor administration “could partially account for the low incidence of severe neutropenia” in the trial, the investigators said.
The study was funded by zanubrutinib marketer Beigene as well as Genentech, the National Cancer Institute, and others. Many of the authors had industry ties, including Dr. Soumerai who reported being a consultant and researcher for Beigene and other companies. Dr. Rossi reported honoraria and research grants from AbbVie, AstraZeneca, and Janssen.
Treatment was stopped in the single-arm phase 2 trial when patients reached undetectable MRD, a novel use of MRD to guide treatment duration. At a median of 16 months after discontinuation, MRD remained undetectable in 31 of 33 patients (94%).
The team also found that a reduction to 1/400 of baseline MRD (delta-MRD400) by day 1 of cycle five predicted undetectable bone marrow MRD within eight treatment cycles.
delta-MRD400 is “a potential biomarker” to identify patients who’ll do well with a shorter treatment and flag others who require longer courses of therapy, said investigators led by Jacob Soumerai, MD, a hematologist/oncologist at Massachusetts General Hospital, Boston.
Overall, the results “are highly encouraging,” they said, with efficacy and safety comparing favorably to trials that added other BTK inhibitors – namely ibrutinib and acalabrutinib – to the standard obinutuzumab/venetoclax backbone, with a shorter treatment duration.
They said the novel triplet warrants further study in the first line and noted that they also “plan to prospectively validate early-MRD-response kinetics as a biomarker to guide treatment duration.” The study was published recently in The Lancet Haematology.
Two editorialists – Davide Rossi, MD, PhD, and Joyce Marques De Almeida, both of the of the Oncology Institute of Southern Switzerland, Bellinzona – were encouraged by the findings and wanted future research to assess how well MRD-guided treatment duration works in patients with tumor protein p53-disrupted disease, who “benefit less from time-limited therapies” then patients with wild-type TP53; the trial was too small to address the issue.
There was a two-cycle lead-in with zanubrutinib and obinutuzumab then venetoclax ramp-up starting at cycle 3, with each cycle running 28 days.
Zanubrutinib is approved in the U.S. for mantle cell lymphoma, Waldenström’s macroglobulinemia, and marginal zone lymphoma.
In a previous phase 2 trial of ibrutinib add-on to venetoclax-obinutuzumab for 14 cycles followed by ibrutinib monotherapy, the rate of undetectable MRD in both peripheral blood and bone marrow was 67%. The rate of bone marrow undetectable MRD was 77% in another phase 2 trial of acalabrutinib, venetoclax, and obinutuzumab for at least 15 cycles.
Dr. Soumerai and his team cautioned, however, that “comparisons across trials are fraught with selection bias resulting in differences in treated patient populations, and randomized data are needed to establish the optimal BTK inhibitor to combine with venetoclax with or without obinutuzumab, and to establish whether” the zanubrutinib triplet “improves progression-free survival and overall survival compared with current standard first-line therapy.”
There was grade 3 or worse neutropenia in 18% of subjects (7/39), one episode of febrile neutropenia (3%), lung infections in three patients (8%) patients, and five cases of hypertension (13%).
The editorialists characterized the numbers as low and the regimen as well tolerated. Past studies of ibrutinib, a first generation BTK, with venetoclax and obinutuzumab have pegged grade 3 or worse neutropenia at 56% and the hypertension incidence at 48%.
Granulocyte colony-stimulating factor administration “could partially account for the low incidence of severe neutropenia” in the trial, the investigators said.
The study was funded by zanubrutinib marketer Beigene as well as Genentech, the National Cancer Institute, and others. Many of the authors had industry ties, including Dr. Soumerai who reported being a consultant and researcher for Beigene and other companies. Dr. Rossi reported honoraria and research grants from AbbVie, AstraZeneca, and Janssen.
FROM THE LANCET HEMATOLOGY
CLL and COVID-19: Outcome trends and lessons learned
Retrospective but the data also highlight areas for further investigation, according to the researchers.
Specifically, “the data highlight opportunities for further investigation into optimal management of COVID-19, immune response after infection, and effective vaccination strategy for patients with CLL,” Lindsey E. Roeker, MD, a hematologic oncologist at Memorial Sloan Kettering Cancer Center, New York, and colleagues wrote in a Nov. 4, 2021, letter to the editor of Blood.
The researchers noted that recently reported COVID-19 case fatality rates from two large series of patients with CLL ranged from 31% to 33%, but trends over time were unclear.
“To understand change in outcomes over time, we present this follow-up study, which builds upon a previously reported cohort with extended follow up and addition of more recently diagnosed cases,” they wrote, explaining that “early data from a small series suggest that patients with CLL may not consistently generate anti–SARS-CoV-2 antibodies after infection.”
“This finding, along with previous reports of inadequate response to vaccines in patients with CLL, highlight significant questions regarding COVID-19 vaccine efficacy in this population,” they added.
Trends in outcomes
The review of outcomes in 374 CLL patients from 45 centers who were diagnosed with COVID-19 between Feb. 17, 2020, and Feb. 1, 2021, showed an overall case fatality rate (CFR) of 28%. Among the 278 patients (75%) admitted to the hospital, the CFR was 36%; among those not admitted, the CFR was 4.3%.
Independent predictors of poor survival were ages over 75 years (adjusted hazard ratio, 1.6) and Cumulative Illness Rating Scale–Geriatric (CIRS) scores greater than 6 (aHR, 1.6).
Updated data for 254 patients diagnosed from Feb. 17 to April 30, 2020, and 120 diagnosed from May 1, 2020, to Feb. 1, 2021, showed that more patients in the early versus later cohort were admitted to the hospital (85% vs. 55%) and more required ICU admission (32% vs. 11%).
The overall case fatality rates in the early and later cohorts were 35% and 11%, respectively (P < .001), and among those requiring hospitalization, the rates were 40% and 20% (P = .003).
“The proportion of hospitalized patients requiring ICU-level care was lower in the later cohort (37% vs. 29%), whereas the CFR remained high for the subset of patients who required ICU-level care (52% vs. 50%; P = .89),” the investigators wrote, noting that “[a] difference in management of BTKi[Bruton’s tyrosine kinase inhibitor]-treated patients was observed in the early versus the later cohort.”
“In the early cohort, 76% of patients receiving BTKi had their drug therapy suspended or discontinued. In the later cohort, only 20% of BTKi-treated patients had their therapy suspended or discontinued,” they added.
Univariate analyses showed significant associations between use of remdesivir and OS (HR, 0.48) and use of convalescent plasma and OS (HR, 0.50) in patients who were admitted, whereas admitted patients who received corticosteroids or hydroxychloroquine had an increased risk of death (HRs, 1.73 and 1.53, respectively).
“Corticosteroids were associated with increased risk of death when the data were adjusted for admission status (HR, 1.8) and the need for mechanical ventilation (HR, 2.0), although they were not significantly associated with survival when the data were adjusted for use of supplemental oxygen (HR, 1.4),” they wrote, also noting that admitted patients treated with corticosteroids in the later cohort did not experience an OS benefit (HR, 2.6).
The findings mirror population-based studies with decreasing CFR (35% in those diagnosed before May 1, 2020, versus 11% in those diagnosed after that date), they said, adding that “these trends suggest that patients in the later cohort experienced a less severe clinical course and that the observed difference in CFR over time may not just be due to more frequent testing and identification of less symptomatic patients.”
Of note, the outcomes observed for steroid-treated patients in the current cohort contrast with those from the RECOVERY trial as published in July 2020, which “may be an artifact of their use in patients with more severe disease,” they suggested.
They added that these data “are hypothesis generating and suggest that COVID-19 directed interventions, particularly immunomodulatory agents, require prospective study, specifically in immunocompromised populations.”
The investigators also noted that, consistent with a prior single-center study, 60% of patients with CLL developed positive anti–SARS-CoV-2 serology results after polymerase chain reaction diagnosis of COVID-19, adding further evidence of nonuniform antibody production after COVID-19 in patients with CLL.
Study is ongoing to gain understanding of the immune response to SARS-CoV-2 vaccination in patients with CLL, they said.
Changing the odds
In a related commentary also published in Blood, Yair Herishanu, MD, and Chava Perry, MD, PhD, of Tel Aviv Sourasky Medical Center called the reduction in mortality over time as reported by Dr. Roeker and colleagues “encouraging and intriguing.”
“One explanation is that the later cohort included a larger proportion of patients with mild symptoms who were diagnosed because of increased awareness of COVID-19 and more extensive screening to detect SARS-CoV-2 over time. That is supported by the lower hospitalization rates and lower rates of hospitalized patients requiring ICU care in the later cohort,” they wrote. “Another possibility is better patient management owing to increasing experience, expanding therapeutic options, and improved capacity of health systems to manage an influx of patients.”
The lower mortality in hospitalized patients over time may reflect better management of patients over time, but it also highlights the significance of “early introduction of various anti–COVID-19 therapies to prevent clinical deterioration to ICU-level care,” they added.
Also intriguing, according to Dr. Herishanu and Dr. Perry, was the finding of increased secondary infections and death rates among corticosteroid-treatment patients.
In the RECOVERY trial, the use of dexamethasone improved survival in patients hospitalized with COVID-19 who received respiratory support. Perhaps the impaired immune reactions in patients with CLL moderate the hyperinflammatory reactions to COVID-19, thus turning corticosteroids beneficial effects to somewhat redundant in this frail population,” they wrote.
Further, the finding that only 60% of patients with CLL seroconvert after the acute phase of SARS-CoV-2 infection suggests CLL patients may be at risk for reinfection, which “justifies vaccinating all patients with CLL who have recovered from COVID-19.”
“Likewise, patients with CLL may develop persistent COVID-19 infection,” they added, explaining that “prolonged shedding of infectious SARS-CoV-2 virus and within-host genomic evolution may eventually lead to emergence of new virus variants.”
Given the high risk of severe COVID-19 disease and impaired antibody-mediated immune response to the virus and its vaccine, a booster dose may be warranted in patients with CLL who fail to achieve seropositivity after 2 vaccine doses, they said.
The available data to date “call for early application of antiviral drugs, [monoclonal antibodies], and convalescent plasma as well as improved vaccination strategy, to improve the odds for patients with CLL confronting COVID-19,” they concluded, adding that large-scale prospective studies on the clinical disease course, outcomes, efficacy of treatments, and vaccination timing and schedule in patients with CLL and COVID-19 are still warranted.
The research was supported by a National Cancer Institute Cancer Center support grant. Dr. Roeker, Dr. Herishanu, and Dr. Perry reported having no financial disclosures.
Retrospective but the data also highlight areas for further investigation, according to the researchers.
Specifically, “the data highlight opportunities for further investigation into optimal management of COVID-19, immune response after infection, and effective vaccination strategy for patients with CLL,” Lindsey E. Roeker, MD, a hematologic oncologist at Memorial Sloan Kettering Cancer Center, New York, and colleagues wrote in a Nov. 4, 2021, letter to the editor of Blood.
The researchers noted that recently reported COVID-19 case fatality rates from two large series of patients with CLL ranged from 31% to 33%, but trends over time were unclear.
“To understand change in outcomes over time, we present this follow-up study, which builds upon a previously reported cohort with extended follow up and addition of more recently diagnosed cases,” they wrote, explaining that “early data from a small series suggest that patients with CLL may not consistently generate anti–SARS-CoV-2 antibodies after infection.”
“This finding, along with previous reports of inadequate response to vaccines in patients with CLL, highlight significant questions regarding COVID-19 vaccine efficacy in this population,” they added.
Trends in outcomes
The review of outcomes in 374 CLL patients from 45 centers who were diagnosed with COVID-19 between Feb. 17, 2020, and Feb. 1, 2021, showed an overall case fatality rate (CFR) of 28%. Among the 278 patients (75%) admitted to the hospital, the CFR was 36%; among those not admitted, the CFR was 4.3%.
Independent predictors of poor survival were ages over 75 years (adjusted hazard ratio, 1.6) and Cumulative Illness Rating Scale–Geriatric (CIRS) scores greater than 6 (aHR, 1.6).
Updated data for 254 patients diagnosed from Feb. 17 to April 30, 2020, and 120 diagnosed from May 1, 2020, to Feb. 1, 2021, showed that more patients in the early versus later cohort were admitted to the hospital (85% vs. 55%) and more required ICU admission (32% vs. 11%).
The overall case fatality rates in the early and later cohorts were 35% and 11%, respectively (P < .001), and among those requiring hospitalization, the rates were 40% and 20% (P = .003).
“The proportion of hospitalized patients requiring ICU-level care was lower in the later cohort (37% vs. 29%), whereas the CFR remained high for the subset of patients who required ICU-level care (52% vs. 50%; P = .89),” the investigators wrote, noting that “[a] difference in management of BTKi[Bruton’s tyrosine kinase inhibitor]-treated patients was observed in the early versus the later cohort.”
“In the early cohort, 76% of patients receiving BTKi had their drug therapy suspended or discontinued. In the later cohort, only 20% of BTKi-treated patients had their therapy suspended or discontinued,” they added.
Univariate analyses showed significant associations between use of remdesivir and OS (HR, 0.48) and use of convalescent plasma and OS (HR, 0.50) in patients who were admitted, whereas admitted patients who received corticosteroids or hydroxychloroquine had an increased risk of death (HRs, 1.73 and 1.53, respectively).
“Corticosteroids were associated with increased risk of death when the data were adjusted for admission status (HR, 1.8) and the need for mechanical ventilation (HR, 2.0), although they were not significantly associated with survival when the data were adjusted for use of supplemental oxygen (HR, 1.4),” they wrote, also noting that admitted patients treated with corticosteroids in the later cohort did not experience an OS benefit (HR, 2.6).
The findings mirror population-based studies with decreasing CFR (35% in those diagnosed before May 1, 2020, versus 11% in those diagnosed after that date), they said, adding that “these trends suggest that patients in the later cohort experienced a less severe clinical course and that the observed difference in CFR over time may not just be due to more frequent testing and identification of less symptomatic patients.”
Of note, the outcomes observed for steroid-treated patients in the current cohort contrast with those from the RECOVERY trial as published in July 2020, which “may be an artifact of their use in patients with more severe disease,” they suggested.
They added that these data “are hypothesis generating and suggest that COVID-19 directed interventions, particularly immunomodulatory agents, require prospective study, specifically in immunocompromised populations.”
The investigators also noted that, consistent with a prior single-center study, 60% of patients with CLL developed positive anti–SARS-CoV-2 serology results after polymerase chain reaction diagnosis of COVID-19, adding further evidence of nonuniform antibody production after COVID-19 in patients with CLL.
Study is ongoing to gain understanding of the immune response to SARS-CoV-2 vaccination in patients with CLL, they said.
Changing the odds
In a related commentary also published in Blood, Yair Herishanu, MD, and Chava Perry, MD, PhD, of Tel Aviv Sourasky Medical Center called the reduction in mortality over time as reported by Dr. Roeker and colleagues “encouraging and intriguing.”
“One explanation is that the later cohort included a larger proportion of patients with mild symptoms who were diagnosed because of increased awareness of COVID-19 and more extensive screening to detect SARS-CoV-2 over time. That is supported by the lower hospitalization rates and lower rates of hospitalized patients requiring ICU care in the later cohort,” they wrote. “Another possibility is better patient management owing to increasing experience, expanding therapeutic options, and improved capacity of health systems to manage an influx of patients.”
The lower mortality in hospitalized patients over time may reflect better management of patients over time, but it also highlights the significance of “early introduction of various anti–COVID-19 therapies to prevent clinical deterioration to ICU-level care,” they added.
Also intriguing, according to Dr. Herishanu and Dr. Perry, was the finding of increased secondary infections and death rates among corticosteroid-treatment patients.
In the RECOVERY trial, the use of dexamethasone improved survival in patients hospitalized with COVID-19 who received respiratory support. Perhaps the impaired immune reactions in patients with CLL moderate the hyperinflammatory reactions to COVID-19, thus turning corticosteroids beneficial effects to somewhat redundant in this frail population,” they wrote.
Further, the finding that only 60% of patients with CLL seroconvert after the acute phase of SARS-CoV-2 infection suggests CLL patients may be at risk for reinfection, which “justifies vaccinating all patients with CLL who have recovered from COVID-19.”
“Likewise, patients with CLL may develop persistent COVID-19 infection,” they added, explaining that “prolonged shedding of infectious SARS-CoV-2 virus and within-host genomic evolution may eventually lead to emergence of new virus variants.”
Given the high risk of severe COVID-19 disease and impaired antibody-mediated immune response to the virus and its vaccine, a booster dose may be warranted in patients with CLL who fail to achieve seropositivity after 2 vaccine doses, they said.
The available data to date “call for early application of antiviral drugs, [monoclonal antibodies], and convalescent plasma as well as improved vaccination strategy, to improve the odds for patients with CLL confronting COVID-19,” they concluded, adding that large-scale prospective studies on the clinical disease course, outcomes, efficacy of treatments, and vaccination timing and schedule in patients with CLL and COVID-19 are still warranted.
The research was supported by a National Cancer Institute Cancer Center support grant. Dr. Roeker, Dr. Herishanu, and Dr. Perry reported having no financial disclosures.
Retrospective but the data also highlight areas for further investigation, according to the researchers.
Specifically, “the data highlight opportunities for further investigation into optimal management of COVID-19, immune response after infection, and effective vaccination strategy for patients with CLL,” Lindsey E. Roeker, MD, a hematologic oncologist at Memorial Sloan Kettering Cancer Center, New York, and colleagues wrote in a Nov. 4, 2021, letter to the editor of Blood.
The researchers noted that recently reported COVID-19 case fatality rates from two large series of patients with CLL ranged from 31% to 33%, but trends over time were unclear.
“To understand change in outcomes over time, we present this follow-up study, which builds upon a previously reported cohort with extended follow up and addition of more recently diagnosed cases,” they wrote, explaining that “early data from a small series suggest that patients with CLL may not consistently generate anti–SARS-CoV-2 antibodies after infection.”
“This finding, along with previous reports of inadequate response to vaccines in patients with CLL, highlight significant questions regarding COVID-19 vaccine efficacy in this population,” they added.
Trends in outcomes
The review of outcomes in 374 CLL patients from 45 centers who were diagnosed with COVID-19 between Feb. 17, 2020, and Feb. 1, 2021, showed an overall case fatality rate (CFR) of 28%. Among the 278 patients (75%) admitted to the hospital, the CFR was 36%; among those not admitted, the CFR was 4.3%.
Independent predictors of poor survival were ages over 75 years (adjusted hazard ratio, 1.6) and Cumulative Illness Rating Scale–Geriatric (CIRS) scores greater than 6 (aHR, 1.6).
Updated data for 254 patients diagnosed from Feb. 17 to April 30, 2020, and 120 diagnosed from May 1, 2020, to Feb. 1, 2021, showed that more patients in the early versus later cohort were admitted to the hospital (85% vs. 55%) and more required ICU admission (32% vs. 11%).
The overall case fatality rates in the early and later cohorts were 35% and 11%, respectively (P < .001), and among those requiring hospitalization, the rates were 40% and 20% (P = .003).
“The proportion of hospitalized patients requiring ICU-level care was lower in the later cohort (37% vs. 29%), whereas the CFR remained high for the subset of patients who required ICU-level care (52% vs. 50%; P = .89),” the investigators wrote, noting that “[a] difference in management of BTKi[Bruton’s tyrosine kinase inhibitor]-treated patients was observed in the early versus the later cohort.”
“In the early cohort, 76% of patients receiving BTKi had their drug therapy suspended or discontinued. In the later cohort, only 20% of BTKi-treated patients had their therapy suspended or discontinued,” they added.
Univariate analyses showed significant associations between use of remdesivir and OS (HR, 0.48) and use of convalescent plasma and OS (HR, 0.50) in patients who were admitted, whereas admitted patients who received corticosteroids or hydroxychloroquine had an increased risk of death (HRs, 1.73 and 1.53, respectively).
“Corticosteroids were associated with increased risk of death when the data were adjusted for admission status (HR, 1.8) and the need for mechanical ventilation (HR, 2.0), although they were not significantly associated with survival when the data were adjusted for use of supplemental oxygen (HR, 1.4),” they wrote, also noting that admitted patients treated with corticosteroids in the later cohort did not experience an OS benefit (HR, 2.6).
The findings mirror population-based studies with decreasing CFR (35% in those diagnosed before May 1, 2020, versus 11% in those diagnosed after that date), they said, adding that “these trends suggest that patients in the later cohort experienced a less severe clinical course and that the observed difference in CFR over time may not just be due to more frequent testing and identification of less symptomatic patients.”
Of note, the outcomes observed for steroid-treated patients in the current cohort contrast with those from the RECOVERY trial as published in July 2020, which “may be an artifact of their use in patients with more severe disease,” they suggested.
They added that these data “are hypothesis generating and suggest that COVID-19 directed interventions, particularly immunomodulatory agents, require prospective study, specifically in immunocompromised populations.”
The investigators also noted that, consistent with a prior single-center study, 60% of patients with CLL developed positive anti–SARS-CoV-2 serology results after polymerase chain reaction diagnosis of COVID-19, adding further evidence of nonuniform antibody production after COVID-19 in patients with CLL.
Study is ongoing to gain understanding of the immune response to SARS-CoV-2 vaccination in patients with CLL, they said.
Changing the odds
In a related commentary also published in Blood, Yair Herishanu, MD, and Chava Perry, MD, PhD, of Tel Aviv Sourasky Medical Center called the reduction in mortality over time as reported by Dr. Roeker and colleagues “encouraging and intriguing.”
“One explanation is that the later cohort included a larger proportion of patients with mild symptoms who were diagnosed because of increased awareness of COVID-19 and more extensive screening to detect SARS-CoV-2 over time. That is supported by the lower hospitalization rates and lower rates of hospitalized patients requiring ICU care in the later cohort,” they wrote. “Another possibility is better patient management owing to increasing experience, expanding therapeutic options, and improved capacity of health systems to manage an influx of patients.”
The lower mortality in hospitalized patients over time may reflect better management of patients over time, but it also highlights the significance of “early introduction of various anti–COVID-19 therapies to prevent clinical deterioration to ICU-level care,” they added.
Also intriguing, according to Dr. Herishanu and Dr. Perry, was the finding of increased secondary infections and death rates among corticosteroid-treatment patients.
In the RECOVERY trial, the use of dexamethasone improved survival in patients hospitalized with COVID-19 who received respiratory support. Perhaps the impaired immune reactions in patients with CLL moderate the hyperinflammatory reactions to COVID-19, thus turning corticosteroids beneficial effects to somewhat redundant in this frail population,” they wrote.
Further, the finding that only 60% of patients with CLL seroconvert after the acute phase of SARS-CoV-2 infection suggests CLL patients may be at risk for reinfection, which “justifies vaccinating all patients with CLL who have recovered from COVID-19.”
“Likewise, patients with CLL may develop persistent COVID-19 infection,” they added, explaining that “prolonged shedding of infectious SARS-CoV-2 virus and within-host genomic evolution may eventually lead to emergence of new virus variants.”
Given the high risk of severe COVID-19 disease and impaired antibody-mediated immune response to the virus and its vaccine, a booster dose may be warranted in patients with CLL who fail to achieve seropositivity after 2 vaccine doses, they said.
The available data to date “call for early application of antiviral drugs, [monoclonal antibodies], and convalescent plasma as well as improved vaccination strategy, to improve the odds for patients with CLL confronting COVID-19,” they concluded, adding that large-scale prospective studies on the clinical disease course, outcomes, efficacy of treatments, and vaccination timing and schedule in patients with CLL and COVID-19 are still warranted.
The research was supported by a National Cancer Institute Cancer Center support grant. Dr. Roeker, Dr. Herishanu, and Dr. Perry reported having no financial disclosures.
FROM BLOOD
Venetoclax heralded a new class of small-molecule blood cancer drugs
Venetoclax’s regulatory approvals, its success as monotherapy for chronic lymphocytic leukemia (CLL) and other lymphoid neoplasms, and its activity in combination against acute myeloid leukemia (AML) have helped pave the way for BCL2 and MCL1 inhibitors that target prosurvival, antiapoptosis proteins.
A first-in-class specific inhibitor of BCL2, A review by Andrew W. Roberts, MD, of the Walter and Eliza Hall Institute of Medical Research, Melbourne, and associates details their key features, including their activity and tolerability and resistance issues. The review was published in Blood .
BH3 mimetics
BH3 mimetics, a new class of small-molecule anticancer drugs, enable specific targeting of BCL2 and MCL1, commonly expressed antiapoptotic proteins in hematologic cancers. The BH3 mimetics inhibit prosurvival BCL2 proteins, enabling activation of the apoptosis effectors BAX and BK that make the outer mitochondrial membranes permeable. This result triggers apoptosis in many cells, while sensitizing others to cell death when the BH3 mimetics are combined with other antineoplastic drugs. The BAX/BAK–driven effect on mitochondrial membranes is to undermine normal energy production, allowing leakage of cell contents, including cytochrome c, a trigger of proteolytic enzymes and cellular demolition.
Navitoclax was the first potent BCL2 inhibitor to enter clinical trials. While it demonstrated moderate single-agent activity in relapsed CLL and indolent B-cell lymphomas, its dose-limiting toxicity of thrombocytopenia precluded further exploration of BCL2 inhibition. Navitoclax is being developed for hematologic disease (for example, myelofibrosis and acute lymphoblastic leukemia). Clinical development of other BH3 mimetics is only in the earliest stages, the authors wrote.
Venetoclax, to avoid this on-target thrombocytopenia, was designed to specifically inhibit BCL2 with great selectivity, a feature not found in naturally occurring BH3-only proteins. The fact that it could inhibit a single prosurvival protein and have important clinical activity proved enormously stimulating to development of this drug class. Potent BH3 mimetics now can also selectively target MCL1, which plays a central role in plasma cells (mature B lymphocytes are highly reliant on BCL2).
In CLL, dependence on BCL2 is high. Venetoclax, since it was first approved by the Food and Drug Administration in April 2016 as monotherapy for relapsed/refractory del(17p) CLL, has been approved widely in combination with rituximab in relapsed/refractory CLL and for unfit patients with newly diagnosed CLL in combination with obinutuzumab. With venetoclax monotherapy, quickly achieved high objective response rates (79%) and complete remissions (20%) revealed the drug’s dose-limiting toxicity of tumor lysis syndrome (TLS). This necessitated gradual ramp-up dosing in those with high disease burden or reduced renal function. Also, despite the adoption of a venetoclax/rituximab combination as standard for relapsed/refractory CLL, the authors underscored that evidence for an additive rituximab benefit is modest and limited.
Resistance
While resistance to venetoclax leading to treatment failure is uncommon in the first year, secondary resistance occurs through several independently occurring mechanisms, including mutations in BCL2 (for example, Gly101Val), overexpression of MCL1, and overexpression of BCLxL. Usual venetoclax therapy is now time limited. Early data on re-exposure shows high rates (about 70%) of secondary responses.
AML
In AML, a more heterogeneous disease than CLL, BCL2 expression varies widely and can be heterogeneous even within a single patient’s leukemic cell population. While responses to venetoclax monotherapy were not durable, combination therapy with azacitidine has revealed enhanced activity. The venetoclax/azacitidine combination has been widely adopted as first-line therapy for older and unfit AML patients. Myelosuppression is the major toxicity.
“As venetoclax is the first in a new class of anticancer drug,” Andrew W. Roberts, MD, said in an interview, “we are still in the process of working out how it can be best utilized. Regimens free of DNA-damaging chemotherapy using this BCL2 inhibitor in combination with obinutuzumab or rituximab in CLL are established. Across B-cell neoplasia (e.g. CLL, mantle cell lymphoma, follicular lymphoma), the challenge is to work out whether venetoclax can enhance other ‘chemotherapy-free’ regimens.” He continued: “In contrast, for AML, learning how venetoclax can be safely combined with intensive chemotherapy is a priority, as we seek to improve outcomes for patients with poor prognosis disease. For MCL1 inhibitors, there is excitement about their potential, but their clinical development remains in its infancy.”
The authors reported multiple financial disclosures.
Venetoclax’s regulatory approvals, its success as monotherapy for chronic lymphocytic leukemia (CLL) and other lymphoid neoplasms, and its activity in combination against acute myeloid leukemia (AML) have helped pave the way for BCL2 and MCL1 inhibitors that target prosurvival, antiapoptosis proteins.
A first-in-class specific inhibitor of BCL2, A review by Andrew W. Roberts, MD, of the Walter and Eliza Hall Institute of Medical Research, Melbourne, and associates details their key features, including their activity and tolerability and resistance issues. The review was published in Blood .
BH3 mimetics
BH3 mimetics, a new class of small-molecule anticancer drugs, enable specific targeting of BCL2 and MCL1, commonly expressed antiapoptotic proteins in hematologic cancers. The BH3 mimetics inhibit prosurvival BCL2 proteins, enabling activation of the apoptosis effectors BAX and BK that make the outer mitochondrial membranes permeable. This result triggers apoptosis in many cells, while sensitizing others to cell death when the BH3 mimetics are combined with other antineoplastic drugs. The BAX/BAK–driven effect on mitochondrial membranes is to undermine normal energy production, allowing leakage of cell contents, including cytochrome c, a trigger of proteolytic enzymes and cellular demolition.
Navitoclax was the first potent BCL2 inhibitor to enter clinical trials. While it demonstrated moderate single-agent activity in relapsed CLL and indolent B-cell lymphomas, its dose-limiting toxicity of thrombocytopenia precluded further exploration of BCL2 inhibition. Navitoclax is being developed for hematologic disease (for example, myelofibrosis and acute lymphoblastic leukemia). Clinical development of other BH3 mimetics is only in the earliest stages, the authors wrote.
Venetoclax, to avoid this on-target thrombocytopenia, was designed to specifically inhibit BCL2 with great selectivity, a feature not found in naturally occurring BH3-only proteins. The fact that it could inhibit a single prosurvival protein and have important clinical activity proved enormously stimulating to development of this drug class. Potent BH3 mimetics now can also selectively target MCL1, which plays a central role in plasma cells (mature B lymphocytes are highly reliant on BCL2).
In CLL, dependence on BCL2 is high. Venetoclax, since it was first approved by the Food and Drug Administration in April 2016 as monotherapy for relapsed/refractory del(17p) CLL, has been approved widely in combination with rituximab in relapsed/refractory CLL and for unfit patients with newly diagnosed CLL in combination with obinutuzumab. With venetoclax monotherapy, quickly achieved high objective response rates (79%) and complete remissions (20%) revealed the drug’s dose-limiting toxicity of tumor lysis syndrome (TLS). This necessitated gradual ramp-up dosing in those with high disease burden or reduced renal function. Also, despite the adoption of a venetoclax/rituximab combination as standard for relapsed/refractory CLL, the authors underscored that evidence for an additive rituximab benefit is modest and limited.
Resistance
While resistance to venetoclax leading to treatment failure is uncommon in the first year, secondary resistance occurs through several independently occurring mechanisms, including mutations in BCL2 (for example, Gly101Val), overexpression of MCL1, and overexpression of BCLxL. Usual venetoclax therapy is now time limited. Early data on re-exposure shows high rates (about 70%) of secondary responses.
AML
In AML, a more heterogeneous disease than CLL, BCL2 expression varies widely and can be heterogeneous even within a single patient’s leukemic cell population. While responses to venetoclax monotherapy were not durable, combination therapy with azacitidine has revealed enhanced activity. The venetoclax/azacitidine combination has been widely adopted as first-line therapy for older and unfit AML patients. Myelosuppression is the major toxicity.
“As venetoclax is the first in a new class of anticancer drug,” Andrew W. Roberts, MD, said in an interview, “we are still in the process of working out how it can be best utilized. Regimens free of DNA-damaging chemotherapy using this BCL2 inhibitor in combination with obinutuzumab or rituximab in CLL are established. Across B-cell neoplasia (e.g. CLL, mantle cell lymphoma, follicular lymphoma), the challenge is to work out whether venetoclax can enhance other ‘chemotherapy-free’ regimens.” He continued: “In contrast, for AML, learning how venetoclax can be safely combined with intensive chemotherapy is a priority, as we seek to improve outcomes for patients with poor prognosis disease. For MCL1 inhibitors, there is excitement about their potential, but their clinical development remains in its infancy.”
The authors reported multiple financial disclosures.
Venetoclax’s regulatory approvals, its success as monotherapy for chronic lymphocytic leukemia (CLL) and other lymphoid neoplasms, and its activity in combination against acute myeloid leukemia (AML) have helped pave the way for BCL2 and MCL1 inhibitors that target prosurvival, antiapoptosis proteins.
A first-in-class specific inhibitor of BCL2, A review by Andrew W. Roberts, MD, of the Walter and Eliza Hall Institute of Medical Research, Melbourne, and associates details their key features, including their activity and tolerability and resistance issues. The review was published in Blood .
BH3 mimetics
BH3 mimetics, a new class of small-molecule anticancer drugs, enable specific targeting of BCL2 and MCL1, commonly expressed antiapoptotic proteins in hematologic cancers. The BH3 mimetics inhibit prosurvival BCL2 proteins, enabling activation of the apoptosis effectors BAX and BK that make the outer mitochondrial membranes permeable. This result triggers apoptosis in many cells, while sensitizing others to cell death when the BH3 mimetics are combined with other antineoplastic drugs. The BAX/BAK–driven effect on mitochondrial membranes is to undermine normal energy production, allowing leakage of cell contents, including cytochrome c, a trigger of proteolytic enzymes and cellular demolition.
Navitoclax was the first potent BCL2 inhibitor to enter clinical trials. While it demonstrated moderate single-agent activity in relapsed CLL and indolent B-cell lymphomas, its dose-limiting toxicity of thrombocytopenia precluded further exploration of BCL2 inhibition. Navitoclax is being developed for hematologic disease (for example, myelofibrosis and acute lymphoblastic leukemia). Clinical development of other BH3 mimetics is only in the earliest stages, the authors wrote.
Venetoclax, to avoid this on-target thrombocytopenia, was designed to specifically inhibit BCL2 with great selectivity, a feature not found in naturally occurring BH3-only proteins. The fact that it could inhibit a single prosurvival protein and have important clinical activity proved enormously stimulating to development of this drug class. Potent BH3 mimetics now can also selectively target MCL1, which plays a central role in plasma cells (mature B lymphocytes are highly reliant on BCL2).
In CLL, dependence on BCL2 is high. Venetoclax, since it was first approved by the Food and Drug Administration in April 2016 as monotherapy for relapsed/refractory del(17p) CLL, has been approved widely in combination with rituximab in relapsed/refractory CLL and for unfit patients with newly diagnosed CLL in combination with obinutuzumab. With venetoclax monotherapy, quickly achieved high objective response rates (79%) and complete remissions (20%) revealed the drug’s dose-limiting toxicity of tumor lysis syndrome (TLS). This necessitated gradual ramp-up dosing in those with high disease burden or reduced renal function. Also, despite the adoption of a venetoclax/rituximab combination as standard for relapsed/refractory CLL, the authors underscored that evidence for an additive rituximab benefit is modest and limited.
Resistance
While resistance to venetoclax leading to treatment failure is uncommon in the first year, secondary resistance occurs through several independently occurring mechanisms, including mutations in BCL2 (for example, Gly101Val), overexpression of MCL1, and overexpression of BCLxL. Usual venetoclax therapy is now time limited. Early data on re-exposure shows high rates (about 70%) of secondary responses.
AML
In AML, a more heterogeneous disease than CLL, BCL2 expression varies widely and can be heterogeneous even within a single patient’s leukemic cell population. While responses to venetoclax monotherapy were not durable, combination therapy with azacitidine has revealed enhanced activity. The venetoclax/azacitidine combination has been widely adopted as first-line therapy for older and unfit AML patients. Myelosuppression is the major toxicity.
“As venetoclax is the first in a new class of anticancer drug,” Andrew W. Roberts, MD, said in an interview, “we are still in the process of working out how it can be best utilized. Regimens free of DNA-damaging chemotherapy using this BCL2 inhibitor in combination with obinutuzumab or rituximab in CLL are established. Across B-cell neoplasia (e.g. CLL, mantle cell lymphoma, follicular lymphoma), the challenge is to work out whether venetoclax can enhance other ‘chemotherapy-free’ regimens.” He continued: “In contrast, for AML, learning how venetoclax can be safely combined with intensive chemotherapy is a priority, as we seek to improve outcomes for patients with poor prognosis disease. For MCL1 inhibitors, there is excitement about their potential, but their clinical development remains in its infancy.”
The authors reported multiple financial disclosures.
FROM BLOOD