Efficacy and safety of bendamustine-containing bridging therapy in R/R LBCL patients receiving CD19 CAR T-cells

Abstract

Bridging therapy (BT) after leukapheresis is required in most relapsed/refractory (R/R) large B-cell lymphoma (LBCL) patients receiving chimeric antigen receptor (CAR) T cells. Bendamustine-containing regimens are a potential BT option. We aimed to assess if this agent had a negative impact on CAR-T outcomes when it was administered as BT. We included R/R LBCL patients from six centers who received systemic BT after leukapheresis from February 2019 to September 2022; patients who only received steroids or had pre-apheresis bendamustine exposure were excluded. Patients were divided into two BT groups, with and without bendamustine. Separate safety and efficacy analyses were carried out for axi-cel and tisa-cel. Of 243 patients who received BT, bendamustine (benda) was included in 62 (26%). There was a higher rate of BT progressors in the non-benda group (62% vs. 45%, p = 0.02). Concerning CAR-T efficacy, complete responses were comparable for benda versus non-benda BT cohorts with axi-cel (70% vs. 53%, p = 0.12) and tisa-cel (44% vs. 36%, p = 0.70). Also, 12-month progression-free and overall survival were not significantly different between BT groups with axi-cel (56% vs. 43% and 71% vs. 63%) and tisa-cel (25% vs. 26% and 52% vs. 48%); there were no differences when BT response was considered. CAR T-cell expansion for each construct was similar between BT groups. Regarding safety, CRS G ≥3 (6% vs. 6%, p = 0.79), ICANS G ≥3 (15% vs. 17%, p = 0.68), severe infections, and neutropenia post-infusion were comparable among BT regimens. BT with bendamustine-containing regimens is safe for patients requiring disease control during CAR T-cell manufacturing.