Higher expansion rate of product T cells measured before infusion (doubling time) is associated with greater in vivo CAR T-cell levels and efficacy and correlates with T-cell phenotype. Logistic regression analysis showing association of response (A) or durable response (B) with doubling time. Doubling time by peak CAR T-cell expansion and peak CAR T-cell expansion normalized to TB (C) or by CAR area under the curve (AUC) (D) were analyzed by quartile analyses. Scatter plots show association of doubling time with specified T-cell populations (E-H) and CD4:CD8 ratio (I). Bar graphs show medians per quartile, and Spearman’s correlation was used to calculate R and P values for all bar graphs and scatter plots.