Successful restoration of checkpoint inhibitors efficacy after allogeneic hematopoietic cell transplant for classic Hodgkin lymphoma patients

Background: Classic Hodgkin lymphoma (cHL) is a highly-curable disease. However, relapses after bone marrow transplant are challenging especially relapses after allogeneic transplant.

Methods: A retrospective chart review of the institution transplant database to summarize the safety and efficacy of checkpoint inhibitors (CPIs) use for cHL relapses postallo-HCT in patients who already failed to derive sustained benefit from CPIs received prior to allo-HCT.

Results: Six cases were identified and reviewed. All patients received and failed to derive sustained benefit from CPIs and brentuximab vedotin preallo-HCT. The median age at the time of allo-HCT was 28.6 years (IQR 23.6-34.2), the median number of lines received prior to allo-HCT was 6.5 (range 5-9). The median duration of CPI therapy prior to allo-HCT was 8.1 months (IQR 6.7-12.9). The median time between the discontinuation of CPI and allo-HCT was 5.78 months (IQR 3.15-15.8). The median time to progression postallo-HCT was 5.75 months (IQR 2.6-11.7). The median time between allo-HCT and re-challenge with a CPI was 7.6 months (IQR 3.2-28.6). The median time of follow up after starting postallo-HCT CPIs was 16 months (IQR 7.25-25.75). Five out six patients responded and two patients developed GvHD.

Conclusion: Our report shows preserved efficacy without any new safety signals by using CPIs postallo-HCT despite using and having failed to derive sustained benefit from CPIs preallo-HCT.