Dose intensity of cyclophosphamide impacts lymphodepletion and CAR T-cell expansion. (A) ALC change before and after HD-Cy and LD-Cy before treatment with CAR T cells (n = 23) demonstrates more significant lymphodepletion in the HD-Cy cohort (P < .001). (B) In vivo CAR T-cell expansion (peak CAR T-cell VCN per milliliter) in peripheral blood was greater in the HD-Cy cohort as compared with the LD-Cy cohort (P = .01).