Updated Keytruda (pembrolizumab) findings in patients with relapsed or refractory primary mediastinal large B-cell lymphoma presented at 58th annual meeting of the American Society of Hematology.
Merck on Monday announced study findings demonstrating that Keytruda (pembrolizumab), the company’s anti-PD-1 therapy, achieved an overall response rate of 41 percent (n=7/17) (90% CI, 21-64) with follow-up of up to 27 months in patients with relapsed or refractory primary mediastinal large B-cell lymphoma (PMBCL), a type of non-Hodgkin lymphoma, who were ineligible for or failed to respond to autologous stem-cell transplantation.
In patients treated with Keytruda, 86 percent of responses (n=6/7) were ongoing at the time of analysis with the median duration of response not yet reached (range: 2 to 23 months). These updated findings, from the ongoing phase 1b KEYNOTE-013 study, were presented at the 58th annual meeting of the American Society of Hematology (ASH) in San Diego.
“For patients with primary mediastinal large B-cell lymphoma who are ineligible for, or fail to respond to, autologous stem-cell transplantation, the prognosis is very poor and there are limited treatment options,” said Pier Luigi Zinzani, M.D., Ph.D., associate professor of hematology, Institute of Hematology “L. e A. Seràgnoli,” University of Bologna. “Based on the rarity of this type of blood cancer, clinical research has been historically limited, and it’s encouraging to see clinical trials conducted in this disease where we are seeing durable responses with Keytruda.”
“We are committed to studying immuno-oncology approaches across a broad spectrum of cancers, including studies in more than 20 hematological subtypes,” said Dr. Roger Dansey, senior vice president and therapeutic area head, oncology late-stage development, Merck Research Laboratories. “These data continue to support the efficacy and safety profile of Keytruda in primary mediastinal large B-cell lymphoma and the importance of ongoing evaluation in this patient population.”
The Keytruda (pembrolizumab) clinical development program includes more than 30 tumor types in nearly 400 clinical trials, including more than 200 trials that combine Keytruda with other cancer treatments. For hematologic malignancies specifically, Merck is conducting broad immuno-oncology research assessing the role of monotherapy and combination regimens with Keytruda. The hematology program includes nearly 40 ongoing studies — including company sponsored, investigator sponsored and collaborative studies; several of these are registration-enabling trials.
KEYNOTE-013 is an ongoing, multi-center, non-randomized, phase 1b trial of approximately 200 patients evaluating the safety, tolerability, and efficacy of Keytruda monotherapy in patients with blood cancers, including myelodysplastic syndromes, multiple myeloma, classical Hodgkin lymphoma, PMBCL and certain other non-Hodgkin’s lymphomas (or lymphomata).
These findings are from a cohort of patients with relapsed or refractory PMBCL who were ineligible for or failed to respond to autologous stem-cell transplantation. The median age was 30.5 years (range: 22 to 62 years). Thirty-three percent of patients had failed prior autologous stem-cell replacement therapy (n=6/18) and 67 percent (n=12/18) were transplant ineligible. The co-primary endpoints of the study were overall response rate and safety; secondary endpoints included duration of response and complete remission rate. Patients were initially treated with Keytruda as monotherapy (10 mg/kg every two weeks) which was later changed by protocol amendment to a fixed dose (200 mg every three weeks). Seventeen patients were included in the efficacy analysis.
Keytruda demonstrated an overall response rate of 41 percent (n=7/17) (90% CI, 21-64), as assessed by International Harmonization Project Response Criteria, with a complete remission rate of 12 percent (n=2/17) (90% CI, 2-33) and a partial remission rate of 29 percent (n=5/17) (90% CI, 12-52). Additionally, 81 percent of patients (n=13/16) had reduction in target lesions. The median duration of follow-up was 11 months (range: 3 to 27 months). At the time of analysis, 86 percent of responses were ongoing (n=6/7) with the median duration of response not yet reached (range: 2 to 23 months). Two patients reached the maximum two years of treatment and remain in remission (follow-up: 25.4 months, 23.8 months).
PMBCL is a rare subtype of diffuse large B-cell lymphoma (a type of non-Hodgkin lymphoma) that arises in the thymus. PMBCL affects young adults in their 30s and 40s and has a slight female predominance. It accounts for 5 to 7 percent of all aggressive lymphomas and two to 3 percent of all non-Hodgkin lymphomas.
(Source: Business Wire)
Filed Under: Drug Discovery