Using the immunotherapy Keytruda (pembrolizumab), a PD-1 inhibitor, prolongs the time without disease progression in patients with relapsed (coming back) or refractory (not responding to treatment) classical Hodgkin lymphoma compared with the current standard of therapy of Adcetris (brentuximab vedotin), an antibody–drug conjugate.
This information is based on results from a phase 3 clinical trial known as KEYNOTE-204, which were presented at the recent 2020 virtual annual meeting of the American Society of Clinical Oncology. The average time without disease progression in these patients was almost 5 months longer with Keytruda compared with Adcetris—13.2 months with Keytruda compared with 8.3 months with Adcetris.
This longer time without disease progression in those using Keytruda was seen in different groups of patients with classical Hodgkin lymphoma, including patients whose disease relapsed after autologous stem-cell transplant, or ASCT, patients who were not eligible for transplant, and patients who had never received Adcetris therapy.
“Based on these findings, pembrolizumab [Keytruda] should be considered the preferred treatment option and new standard of care for relapsed or refractory classical Hodgkin lymphoma in patients who have relapsed post-ASCT or are ineligible for ASCT,” said John Kuruvilla, MD, FRCPC, with Princess Margaret Cancer Centre in Toronto, Canada.
The current standard of care for patients with relapsed or refractory classical Hodgkin lymphoma is chemotherapy, a transplant, and Adcetris, which is also used as the first-line therapy for patients with this type of lymphoma.
This study included 304 patients who were divided equally into 2 groups. One group received Keytruda immunotherapy and the other group received Adcetris. The average follow-up period was 24.7 months.
The results showed that Keytruda significantly improved the time without disease progression compared with Adcetris and reduced the risk for disease progression or death by 35%. Specifically, immunotherapy with Keytruda reduced the risk for disease progression or death by 39% in patients who did not have a transplant; by 48% in patients with refractory disease; by 66% in patients who had previously received Adcetris; and by 33% in patients who had not received Adcetris previously.
Among patients who had a response to therapy, the response lasted 20.7 months with Keytruda compared with 13.8 months with Adcetris.
Serious side effects (grade 3 or 4) related to the treatment were reported in 19.6% of the patients receiving immunotherapy and 25% with Adcetris. However, 1 death was reported in the immunotherapy group from serious pneumonia.
Immune-mediated side effects that are associated with immunotherapy were higher in the pembrolizumab group; the most common of these side effects were hypothyroidism (18.9%) and pneumonitis (10.8%).