Pembrolizumab provided durable and deep responses with acceptable tolerability in a broad spectrum of RRcHL.
Pembrolizumab was also effective in difficult-to-treat chemorefractory cHL.
Programmed death-1 inhibitors are approved for patients with relapsed or refractory classic Hodgkin lymphoma (RRcHL). We present the 2-year follow-up of the phase 2 KEYNOTE-087 study of pembrolizumab in 210 patients, based on HL progression after autologous stem cell transplantation (ASCT) and subsequent brentuximab vedotin (BV; cohort 1); salvage chemotherapy and BV, with ineligibility for SCT owing to chemorefractory disease (cohort 2); and progression after SCT without BV (cohort 3). With a median follow-up of 27.6 months, the objective response rate (ORR) by blinded independent central review was 71.9% (95% CI, 65.3-77.9), the complete response rate (CRR) was 27.6%, and the partial response (PR) rate was 44.3%. Median duration of response was 16.5 months (range, 0.0+ to 27.0+ [+, no progressive disease at last assessment]) in all patients, 22.1 months in cohort 1, 11.1 months in cohort 2, and 24.4 months in cohort 3. Median progression-free survival was not reached in all patients with CR: 13.8 months (95% CI, 12.0-22.1) for patients with PR and 10.9 months (95% CI, 5.6-11.1) for patients with stable disease. Median overall survival was not reached in all patients or in any cohort. Treatment-related adverse events (TRAEs) of any grade occurred in 153 (72.9%) patients; grades 3 and 4 occurred in 25 (12.0%) patients; none resulted in death. Results confirmed effective antitumor activity, durability of response, and manageable safety of pembrolizumab monotherapy in RRcHL, regardless of prior treatment and including chemoresistant cHL. This trial was registered at www.clinicaltrials.gov as #NCT02453594.