EHA 2023 | The impact of bendamustine bridging therapy on the safety and efficacy of CAR-T therapy in LCBL

So we presented last year some data regarding the use of bendamustine before the CAR-T cell apheresis at ASH 2022, and we confirmed that it has a deleterious effect on CAR-T cell efficacy. So then we asked the question: does bendamustine as bridging also have a negative effect on CAR-T cell efficacy? Could it potentially affect the non-CAR-T cell compartment and impact CAR-T cell expansion? So, we analyzed over 300 patients who had received commercial CAR-T cells. These patients were bendamustine-naive, that is to say they had not received bendamustine before apheresis. And we excluded patients who did not receive bridging or had received radiotherapy as bridging. So included only bendamustine-naive patients who received a systemic form of bridging therapy, and then we divided them amongst those who had bendamustine in their bridging strategy and those who did not. Mostly the bendamustine-containing regimens were rituximab, polatuzumab, bendamustine.

What we observed between these two groups and also according to construct – so we took that into account – is that there did not seem to be a negative impact of bendamustine-containing regimens in the bridging context regarding CAR-T cell efficacy, CAR-T cell safety or CAR-T cell expansion. So, patients who received the bendamustine as bridging and had not received it prior to apheresis had similar outcomes regarding both safety and efficacy and similar CAR-T cell expansion peaks and area under the curve. So our take home message would be that bendamustine, as part of the bridging strategy, does not seem to have negative impact and therefore the goal is to gain the best disease control possible with bridging therapy to lower tumor burden and make sure that the patient gets to CAR-T cell therapy in the best possible condition.