The FDA approved the anti-PD-1 monoclonal antibody pembrolizumab for adults and children with classic Hodgkin lymphoma who are refractory to treatment or who have relapsed after receiving ≥3 prior lines of therapy. This is the only anti-PD-1 therapy approved for this patient population.
The approval was based on results from the KEYNOTE-087 trial, which included 210 patients who received pembrolizumab 200 mg every three weeks. Many patients (58%) were refractory to their previous therapy, including 35 percent who had primary-refractory disease and 14 percent whose disease was chemotherapy-refractory to all prior regimens. Prior treatments included hematopoietic cell transplantation (HCT; 61%) and radiation therapy (36%); 17 percent of patients had not received brentuximab vedotin.
After a median follow-up of 9.4 months, the overall response rate (ORR) was 69 percent (95% CI 62-75), which included a complete remission rate of 22 percent and a partial remission rate of 47 percent. The median duration of response among the 145 patients who responded to therapy was 11.1 months (range = 0-11.1 months).
The most common treatment-related AEs included fatigue (26%), pyrexia (24%), cough (24%), musculoskeletal pain (21%), diarrhea (20%), and rash (20%). Serious AEs occurred in 16 percent of patients, the most common of which were pneumonia, pneumonitis, pyrexia, dyspnea, graft-versus-host disease (GVHD), and herpes zoster.
Five percent of patients discontinued therapy because of AEs, and 26 percent experienced treatment interruption. Two patients died from GVHD after subsequent allogeneic HCT and septic shock.
Source: Merck news release, March 14, 2017.