Long-term survival with donor CD19 CAR-T cell treatment for relapsed patients after allogeneic hematopietic stem cell transplantation.

Chimeric Antigen Receptor T (CAR-T) cell therapy has significantly advanced in treating B-cell acute lymphoblastic leukemia (B-ALL) and has shown efficacy in managing relapsed B-ALL after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Donor-derived CAR-T cell offer both high efficacy and rapid response. Although promising results exist, current research lacks definitive evidence of long-term survival benefits for patients treated with donor-derived CAR-T therapy. We report the long-term survival of 32 patients with post-transplant relapsed B-ALL treated with donor-derived CD19 CAR-T cell, achieving either complete Remission (CR) or CR with incomplete peripheral blood recovery (CRi). The median follow-up was 42 months, with 2-year overall survival (OS) and event-free survival (EFS) rates of 56.25% and 50.0%, respectively. The 5-year OS and EFS rates were 53.13% and 46.88%, with no new long-term adverse events observed. These findings demonstrate good long-term safety, supporting donor-derived CAR-T cell as a recommended treatment option for relapsed B-ALL patients post-transplantation. Trial registration: https://www.chictr.org.cn/showproj.html?proj=14315 . Registration number: ChiCTR-OOC-16008447.