Effectiveness of chemotherapy after anti‐PD‐1 blockade failure for relapsed and refractory Hodgkin lymphoma.

Programmed death‐1 (PD1) blockade is an efficient and safe therapeutic option in patients with relapsed/refractory (R/R) classical Hodgkin lymphoma (cHL). However, a substantial proportion of patients' progresses or loses the response to anti‐PD1 treatment. We retrospectively investigated the effectiveness of salvage chemotherapies (CHT) for unsatisfactory response to anti‐PD1, in 25 R/R cHL patients. Twenty‐three patients (92%) were refractory to the last treatment before anti‐PD1. After a median of 14 cycles (range 3‐52), 68% (17/25) of patients had unsatisfactory responses to anti‐PD1 therapy, whereas 6 had a partial response (PR) and 2 patients achieved complete response (CR), with an overall response rate (ORR) of 32%. After a median time of 1.5 months, 15 patients received a single agent treatment and 10 had a multi‐agents regimen, due to the failure of PD1 blockade. The ORR was 60% (8 CR and 7 PR). Seven patients (3 in PR and 4 in CR) underwent a consolidation strategy with stem cell transplantation. Median progression‐free survival (PFS) with salvage treatment was reached at 19.1 months, while median PFS after anti‐PD1 has been reached at 8.2 months. After a median follow‐up of 32.4 months, 6 patients died while 13 are still in CR. The median overall estimated from the start of CHT was not reached. The efficacy of treatment following anti‐PD1 is not yet established, especially in lymphoma patients. To note, in our series, a subset of heavily pre‐treated and chemo‐refractory patients increased response rates to and survival with CHT given after exposure to immune‐checkpoint inhibitors. [ABSTRACT FROM AUTHOR]