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

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.