[Cohort study of efficacy and safety of polatuzumab vedotin combined with immunochemotherapy in patients with relapse/refractory diffuse large B cell lymphoma].

Objective: To investigate the efficacy and tolerability of Polatuzumab vedotin+rituximab±bendamustine (Pola-(B)R) in relapse/refractory diffuse large B cell lymphoma (R/R DLBCL) patients. Methods: The clinical data of 21 patients enrolled in Chinese Pola compassionate use program (CUP) in 4 centers from November 2019 to August 2020 were collected. There were 15 males and 6 females, and the median age was 56 years (ranged 25-76 years). Of the patients, 10 cases received Pola-BR regimen and the other 11 received Pola-R. Their clinical features, regimens, efficacy, and adverse events (AEs) were retrospectively analyzed. Results: Twenty-one patients with at least one efficacy evaluation were included. At data analysis cut-off point (12 Aug. 2020), the best overall response (BOR) rate was 81.0% (17/21) and the complete response (CR) rate was 19.0% (4/21). Kaplan-Meier survival estimation was performed, at a median follow-up of 54 days, three patients (14.3%) had disease progressed, and 18 patients (85.7%) were censored; the median progression-free survival (mPFS) was estimated to be 148 days. The incidence of adverse effects (AEs) of any grade was higher in Pola-BR group than Pola-R group (80.0% vs 63.6%). However, the incidence of grade 3-4 AEs were close in the two groups (30.0% vs 29.3%). The most common hematological toxicities were thrombocytopenia (28.6%, 6/21), neutropenia (28.6%, 6/21) and anemia (14.3%, 3/21), respectively. One patient with pneumonia and 1 patient with hemophagocytic syndrome recovered after symptomatic treatment. No peripheral neuropathy of grade≥2 was observed. Conclusions: The preliminary data suggested that, for heavily treated Chinese R/R DLBCL, the Pola-(B)R regimen still achieves promising efficacy and tolerable safety.