Real-world outcomes of the efficacy and safety of polatuzumab vedotin combination regimen in patients with relapsed/refractory diffuse large B cell lymphoma

Abstract

Objective Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL), with approximately 60% of patients being successfully treated with R-CHOP therapy. However, a significant proportion, around 40%-45%, do not respond to initial treatment or experience relapse, leading to a poor prognosis for this patient group. Therefore, the exploration of targeted drugs and combination therapies is crucial. Among these options, polatuzumab vedotin (Pola), an anti-CD79B antibody-drug conjugate (ADC), shows promise and plays a significant role in combination therapy. Two of the most promising combination regimens involving Pola-bendamustine and rituximab (Pola-BR) and Pola-rituximab + cyclophosphamide + doxorubicin/epirubicin + prednisone (Pola-RCHP). We aim to analyze the efficacy and safety of Pola combined with BR and Pola combined with R-CHP in the treatment of relapsed/refractory DLBCL (R/R DLBCL). Methods This retrospective study aimed to assess the efficacy and safety of the Pola-based combination regimen at our center during the period from May 1, 2023, to September 30, 2023. Eligible participants were patients with R/R DLBCL, with Ann Arbor stages 3-4, aged between 36 to 88 years, and who had previously undergone at least one standard chemotherapy regimen. We conducted a retrospective analysis of clinical data from 19 patients who were enrolled in our center during the specified period, consisting of 11 males and 8 females. The median age of these patients was 65 years, with an age range of 36 to 88 years. Out of the 19 patients, 13 were treated with Pola-BR, while 6 received Pola-R-CHP. We examined various clinical characteristics, medication regimens, treatment efficacy, and the occurrence of adverse reactions. The primary objective of this study is to investigate and understand the factors contributing to adverse events in both the Pola-BR and Pola-R-CHP treatment groups. Results As of September 30, 2023, in the efficacy evaluation of 19 patients, the overall response rate (ORR) was 68.4% (13/19), and the complete response (CR) rate was 52.6% (10/19). Progression-free survival (PFS) with a median follow-up of 45 days showed that 3 cases (12%) experienced disease progression. When comparing the Pola-RCHP group to the Pola-BR group, a lower incidence of adverse reactions was observed. The primary adverse event reported was pulmonary infection, with 38.5% (5/13) occurring in the Pola-BR group and 16.7% (1/6) in the Pola-R-CHP group. It’s worth noting that no severe pneumonia cases occurred in either group. Conclusion Compared to the traditional R-CHOP regimen, the combination of Pola with BR/RCHP appears to offer superior therapeutic efficacy and more promising prospects for the treatment of patients with R/R DLBCL.