未经体外处理的单倍体造血干细胞移植是儿童及年轻成人 CAR-T 细胞治疗后复发/难治性费城染色体阴性 B 细胞急性淋巴细胞白血病的优选方案

Although chimeric antigen receptor T-cell (CAR-T) therapy produces a high complete remission rate among patients with relapsed/refractory B-cell acute lymphoblastic leukemia, relapse remains an urgent issue. It is uncertain whether consolidative haploidentical-allogeneic hematopoietic stem cell transplantation (haplo-HSCT) is suitable for achieving sustainable remission.

Therefore, we aimed to assess the efficacy and safety of bridging CAR-T therapy to haplo-HSCT. Fifty-two patients with relapsed/refractory Philadelphia chromosome-negative B-cell acute lymphoblastic leukemia who underwent haplo-HSCT after CAR-T therapy were analyzed. The median time from CAR-T therapy to haplo-HSCT was 61 days. After a median follow-up of 24. 6 months, the 1-year probabilities of event-free survival, overall survival, and cumulative incidence of relapse were 80. 1% (95% confidence interval (CI), 69. 0-90. 9), 92. 3% (95% CI, 85. 0-99. 5), and 14. 1% (95% CI, 10. 7-17.

4), respectively, while the corresponding 2-year probabilities were 76. 0% (95% CI, 64. 2-87. 7), 84. 3% (95% CI, 74. 3-94. 3), and 19. 7% (95% CI, 15. 3-24. 0), respectively. No increased risk of 2-year cumulative incidence of graft-versus-host disease, treatment-related mortality, or infection was observed.

A pre-HSCT measurable residual disease-positive status was an independent factor associated with poor overall survival (hazard radio: 4. 201, 95% CI: 1. 034-17. 063; P = 0. 045). Haplo-HSCT may be a safe and effective treatment strategy to improve event-free survival and overall survival after CAR-T therapy.