A retrospective cohort study of polatuzumab vedotin combined with immunochemotherapy in Chinese patients with relapse/refractory diffuse large B cell lymphoma

BACKGROUND: There are no standard therapies for patients with relapse/refractory diffuse large B-cell lymphoma (R/R DLBCL) who are ineligible for transplantation. Recently, polatuzumab vedotin (pola) combined with rituximab and bendamustine (pola-BR) has been validated in clinical trials. However, pola is not approved in China and clinical data in Chinese population is still lacking. This study is intended to preliminarily evaluate the clinical effectiveness of this regimen in China. METHODS: This study retrospectively evaluated the efficacy and tolerability of pola-BR regimen in Chinese R/R DLBCL patients treated in a compassionate use program (CUP; pola CUP) after failing ≥2 prior regimens. Patients participated in CUP at 4 Chinese centers from December 2019 to July 2020 were enrolled. The outcomes were the overall response rate (ORR), complete response (CR) rate, and progression-free survival (PFS). Adverse events (AEs) were collected. RESULTS: A total of 28 patients enrolled in the pola CUP were included. At data analysis cut-off (30 September 2020), the best overall response (BOR) rate was 71.4%, and a CR rate of 25.0% was obtained. The estimated median PFS of all patients was 200 [95% confidence interval (CI): 97 to not evaluable (NE)] days. The most common AEs were thrombocytopenia (32.1%), neutropenia (28.6%), and fever (14.3%). High-grade (grade ≥2) peripheral neuropathy (PN) was not observed. CONCLUSIONS: These preliminary data suggested that the pola-BR regimen has promising efficacy and tolerable safety in Chinese transplantation ineligible R/R DLBCL patients. Hence, pola-BR may be an optional regimen. Considering the limited sample size and short follow-up, larger sample and long-term survival outcome studies are warranted.