Real-world outcomes for young adult patients receiving CD19 CAR T-cell therapy

Tisagenlecleucel (tisa-cel) and brexucabtagene autoleucel (brexu-cel) are approved CD19 chimeric antigen receptor T-cell therapy (CAR T) products for young adults (YA) with relapsed/refractory B-cell acute lymphoblastic leukemia. A distinct analysis of YAs receiving commercial CD19 CAR T has not been reported. Using retrospective data from the Pediatric Real-World CAR T Consortium and the Real-World Outcomes of CAR T in Adult ALL collaboration, we describe the efficacy and safety of tisa-cel and brexu-cel in 70 YAs (18-26 years; tisa-cel, n = 50; brexu-cel, n = 20). Cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were observed more frequently for brexu-cel vs tisa-cel (CRS, 85% vs 56%; ICANS, 40% vs 18%). Complete response rates were similar between products at 80% for brexu-cel and 88% for tisa-cel. Relapse-free survival (RFS) at 12 months was 46% for brexu-cel and 36% for tisa-cel. Durability of remission over 12 months was 61% for brexu-cel vs 41% for tisa-cel; 12-month overall survival (OS) for brexu-cel was 84% vs 68% for tisa-cel. In multivariate analysis, low disease burden was associated with improved OS, whereas inotuzumab before CAR T was associated with inferior outcomes. This study demonstrates comparable real-world efficacy among YAs receiving CD19 CAR T irrespective of CAR T construct; however, rates of toxicity seem higher with brexu-cel.