https://orcid.org/0000-0003-2385-7085
Key Points
Immune checkpoint inhibitor before allogeneic transplantation in Hodgkin lymphoma improves overall survival when compared to chemotherapy
Immune checkpoint inhibitor increases the risk of grade III-IV acute GVHD which may be abrogated by increasing immunosuppression
Patients with relapsed classic Hodgkin lymphomas receive salvage therapy with immune checkpoint inhibitors (ICI) or chemotherapy (no-ICI). Patients responding to therapy often undergo consolidation with allogeneic blood or marrow transplantations (alloBMT). We previously reported that relapsed cHL patients treated with ICI followed by alloBMT experienced improved 3-year progression-free survival (PFS) compared to patients treated with salvage chemotherapy without ICI, followed by alloBMT. In this retrospective analysis, we report the 5-year OS, PFS, and GVHD incidence in cHL patients treated with ICI before alloBMT with post-transplantation cyclophosphamide (PTCy) GVHD prophylaxis. Among the 147 relapsed/refractory patients with cHL, 71 (48.3%) received ICIs and 76 (51.7%) received chemotherapy without ICIs (no-ICI) before alloBMT. We observed an improved 5-year estimated OS of 91% (ICI) versus 66% (no-ICI), (hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.16 to 0.98; P = 0.046) and a 5-year estimated PFS of 84% (ICI) versus 53% (no-ICI) (HR, 0.4; 95% CI, 0.2 to 0.81; P = 0.011). The 12-month cumulative incidence of grade III-IV GVHD was 20% (ICI) and 7% (no-ICI) (SDHR 3.16; 95% CI, 1.13 to 8.81 p = 0.03. More frequent grade III-IV acute GVHD was likely due to the higher incidence of grade III-IV acute GVHD in the subset of patients with pre-transplant exposure to ICI and shortened duration (60 days) of immunosuppression versus patients with long immunosuppression (day 180). These data suggest that cHL patients treated with ICI and alloBMT experience improved OS and the GVHD risk can be mitigated by immunosuppression until day 180.
