CXCR4 induces memory formation over exhaustion in CAR-T cells to achieve durable leukemia targeting

Chimeric antigen receptor (CAR)-T cell therapy has transformed the treatment of B-cell malignancies, but its success in acute myeloid leukemia (AML) remains limited. Durable responses depend on the formation of long-lived memory T cells, whereas T cell exhaustion contributes to non-response and relapse. In patients with AML who achieved remission after cord blood transplantation, we here first observe enrichment of memory T cells with high expression of the chemokine receptor CXCR4. Next, we show that engineering CAR-T cells to co-express CXCR4 enhances their persistence and anti-leukemic activity in patient-derived xenograft models. Using single-cell profiling and metabolic analysis, we find that CXCR4 promotes memory-associated transcriptional programs, reduces exhaustion, and supports oxidative metabolism. These effects are observed with CAR-T cells targeting CD25 or CD96 as AML-associated targets. Our results indicate that CXCR4 strengthens CAR-T cell memory and durability, offering a strategy to improve immunotherapy outcomes in AML and beyond.