Outcomes of pirtobrutinib for relapsed/refractory mantle cell lymphoma in compassionate use program in Europe

Background Mantle cell lymphoma (MCL) is a type of B‐cell lymphoma that is currently incurable. Pirtobrutinib shows promising response rates in heavily pretreated MCL patients according to the approval study, but the real‐world data are scarce. Methods In this study, we retrospectively analyzed the efficacy and safety profile of pirtobrutinib in 10 relapsed/refractory MCL patients from compassionate use program (CUP). Results On average, the patients underwent three lines of systemic therapy prior to pirtobrutinib and were predominantly BTKi exposed (9/10). The best overall response rate (BORR) was 67%. In a median follow‐up of 8.6 months, the mean duration of response (DOR), progression‐free survival (PFS), and overall survival (OS) were not reached. No new safety signals were documented. Conclusions In summary, pirtobrutinib represented a safe and effective treatment option in a small real‐world population. Data describing outcomes of pirtobrutinib in patients with relapsed/refractory mantle‐cell lymphoma (r/r MCL) in clinical routine are lacking. Here, we present the findings of a real‐world data study including 10 patients with heavily pretreated r/r MCL (median 3 therapy lines prior) who underwent treatment with pirtobrutinib as part of the compassionate use patient program (CUP) in Germany, Austria, and Switzerland. Best overall response rate was 70%. One‐year PFS and OS were 56% and 70%, accordingly. No new safety signals were documented. The outcomes observed in our study were encouraging and similar to those reported in the pivotal study.