M.D. Anderson experience of immune checkpoint inhibitor therapy in classical Hodgkin lymphoma.

Abstract

e20013 Background: Nivolumab and Pembrolizumab are effective immune checkpoint inhibitor (ICI) therapies targeting PD-1/ PDL-1 immune axis. The drugs are currently approved for relapsed/ refractory classical Hodgkin lymphoma (cHL)based on phase I and II trial data. Methods: We conducted a retrospective study of patients (pts) with relapsed refractory cHL treated with ICI therapy at M.D. Anderson Cancer center from 4/2013 to 5/2019 to evaluate the efficacy of this treatment. The responses were assessed using revised response criteria according to the Lugano classification Results: Ninety-two pts treated with nivolumab (66) and pembrolizumab (26) were included. Fifty six pts (63%) were advanced stage at diagnosis, most treated initially with ABVD (88%) and BV-AVD (3%). Seventy percent pts had primary refractory disease or relapsed < 12 months after frontline therapy. At the time of ICI initiation, pts had the following characteristics: median age 35 (range 18-86), extranodal disease - 28 pts (37%), prior BV exposure in 81 pts (89%) with 66% considered BV refractory. Sixty one percent patients were refractory to the last prior line of salvage therapy. Median prior lines of therapy was of 3 (range 1-13) and 53 pts (58%) had a prior HSCT. At a median follow-up time of 20.2 months (range: 1.58 - 55.98 months), median progression free survival was 12.3 months and median overall survival was not reached. Among the 39 patients with no prior transplant, 11 patients who achieved CR with ICI were consolidated with HSCT (autologous - 7 and allogeneic - 4). Of this cohort, 2 pts (1 post auto, 1 post-allo) have relapsed. Five patients in our cohort were treated with an alternative ICI for subsequent relapse; of four patients with response assessment, 3 achieved CR and 1 experienced PD. Conclusions: In this cohort of cHL pts, ICI offered high response rates before and after HSCT supporting the possibility for using ICI earlier in the treatment course for refractory or early relapsed HL.