Abstract
Infants with B-cell acute lymphoblastic leukemia (B-ALL) have poor outcomes because of chemotherapy resistance leading to high relapse rates. Tisagenlecleucel, a CD19-directed chimeric antigen receptor T-cell (CART) therapy, is US Food and Drug Administration approved for relapsed or refractory B-ALL in patients ≤25 years; however, the safety and efficacy of this therapy in young patients is largely unknown because children <3 years of age were excluded from licensing studies. we retrospectively evaluated data from the pediatric real-world car consortium to examine outcomes of patients with infant b-all who received tisagenlecleucel between 2017 and 2020 (n="14)." sixty-four percent of patients (n="9)" achieved minimal residual disease-negative remission after cart and 50% of patients remain in remission at last follow-up. all patients with high disease burden at time of cart infusion (>M1 marrow) were refractory to this therapy (n = 5). Overall, tisagenlecleucel was tolerable in this population, with only 3 patients experiencing ≥grade 3 cytokine release syndrome. No neurotoxicity was reported. This is the largest report of tisagenlecleucel use in infant B-ALL and shows that this therapy is safe and can be effective in this population. Incorporating this novel immunotherapy into the treatment of infant B-ALL offers a promising therapy for a highly aggressive leukemia. International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.3>