Cumulative incidence of time to serum total IgG <400 mg/dL post–CD19-CARTx among participants with IgG ≥400 mg/dL pre–CD19-CARTx. This figure includes 22 participants with IgG concentrations ≥400 mg/dL pre–CD19-CARTx who also had IgG measurements post–CD19-CARTx. (A) The overall cumulative incidence of IgG <400 mg/dL by day 365 was 60% (95% CI, 38-82). The shaded area represents the upper and lower limits of the 95% CIs. The cumulative incidence of IgG <400 mg/dL varied by underlying disease (P = .06) (B) but was similar by age (P = .8) (C) and prior HCT (P = .9) (D).