Efficacy and tolerability of nivolumab after allogeneic transplantation for relapsed Hodgkin lymphoma.

Allogeneic hematopoietic cell transplantation (allo-HCT) is indicated for patients with relapsed or refractory Hodgkin lymphoma (HL). Although long-term disease control can be achieved, relapse is still frequent. The programmed cell death protein 1 (PD-1) pathway-blocking antibody nivolumab has shown substantial therapeutic activity and an acceptable safety profile in patients with relapsed or refractory HL who did not receive allo-HCT. However, PD-1 blocking strategy can increase the risk of graft-versus-host disease (GVHD) in murine models. We retrospectively assessed the efficacy and toxicity of nivolumab as a single agent in 20 HL patients relapsing after allo-HCT. GVHD occurred in 6 patients (30%) after nivolumab initiation. All 6 patients had prior history of acute GVHD. The patients with nivolumab-induced GVHD were managed by standard treatment for acute GVHD. Two patients died as a result of GVHD, 1 of progressive disease and 1 of complications related to a second allo-HCT. Overall response rate was 95%. At a median follow-up of 370 days, the 1-year progression-free survival rate was 58.2% (95% CI, 33.1%-76.7%) and the overall survival rate was 78.7% (95% CI, 52.4%-91.5%). Among 13 patients still in response, 6 received a single dose of nivolumab and 7 remain on nivolumab. Compared with standard options for this indication, our results show that nivolumab is effective with an acceptable safety profile.