CAR-T bridging to allo-HSCT as a treatment strategy for relapsed adult acute B-lymphoblastic leukemia: a case report

BACKGROUND: Adults with relapsed acute lymphoblastic leukemia (ALL) have a poor prognosis, especially in patients who relapsed within 6 months of complete remission 1 (CR1). Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the treatment of choice. However, this can only be considered after complete remission 2 (CR2) is achieved. Therefore, bridging treatment is urgently needed. CASE PRESENTATION: In the present study, we report a relapsed adult B-cell ALL case that achieved CR2 after treatment with CD19-directed chimeric antigen receptor (CAR)-modified T cell (CAR-T) therapy. After subsequent allo-HSCT, the patient acquired 21 months of disease-free survival. CONCLUSION: The present results confirm that both CAR-T and allo-HSCT are effective for treating refractory or relapsed B-ALL. However, a novel sequential treatment strategy with these two therapeutic methods may achieve longer disease-free survival time.