A Comparison Study of Anti-CLL1 CART Cells Equipped with Different Co-Stimulatory Domains in the Treatment of Children with Refractory/Relapsed Acute Myeloid Leukemia

Background: It's well established that conventional chemotherapy doesn't benefit children with refractory/relapsed acute myeloid leukemia (R/R-AML). Though multiple attempts, i.e., novel target agents, and intensive chemotherapy, have been translated into clinics, few have been proved to be successful. Chimeric antigen receptor (CAR) T cell therapy is increasingly becoming a curative candidate for refractory hematological malignancies. Recently, anti-CLL1 CAR T-cells have been reported to effectively treat children with R/R-AML by several groups even though with a small sample size. However, the impact of co-stimulatory domain (CD28/CD27 versus 4-1BB) on the efficacy of CAR T-cells could not be neglected, which is not investigated so far. Thus, we here compare the impact of different costimulatory molecules on the safety and efficacy of anti-CLL1 CAR T-cells in treating children with R/R-AML.