An exceptional case of durable remission achieved with reinfusion of CD19-directed CAR-T despite failure to induce B-cell aplasia and review of institutional experience with reinfusion of tisagenlecleucel

CD19-directed chimeric antigen receptor T lymphocytes (CAR-T) have led to durable remissions in children with refractory and/or multiply relapsed B-lymphoblastic leukemia. For those who relapse or lose B-cell aplasia post-CAR-T, the role of CAR-T reinfusion is unclear. We report a case of durable remission with tisagenlecleucel reinfusion despite failure to achieve B-cell aplasia and compare this case to seven additional children who received multiple tisagenlecleucel infusions at our institution. Our experience suggests that reinfusion is safe and may be a definitive therapy for a small subset of patients. Reinfusion can also reintroduce remission and/or B-cell aplasia, allowing for subsequent therapies.