Modern chemotherapy for pediatric acute B-lymphoblastic leukemia (B-ALL), including a maintenance phase on the backbone of oral antimetabolite administration, has resulted in a generally excellent prognosis for newly diagnosed disease. However, therapy-related toxicities may preclude a patient’s ability to safely receive traditional chemotherapy. We report the case of a child with B-ALL unable to tolerate oral antimetabolite therapy due to recurring necrotizing pancreatitis secondary to asparaginase. She received a modified maintenance therapy with blinatumomab, a CD3- and CD19-directed bispecific T-cell engager antibody, which was well tolerated and allowed for resolution of her pancreatitis while maintaining a durable remission.

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.