Cumulative incidence of GR2-4 aGVHD divided by C_{trough_1}. (A) Cumulative incidence of GR2-4 aGVHD for patients receiving placebo and those with C_{trough_1} <39 μg/mL (pink) vs those with a C_{trough_1} ≥39 μg/mL (green) (developmental cohort). (B) Cumulative incidence of GR2-4 aGVHD for patients receiving placebo and those with C_{trough_1} <39 μg/mL (pink) vs those with a C_{trough_1} ≥39 μg/mL (green) (validation cohort). (C) Cumulative incidence of GR2-4 aGVHD for patients receiving placebo (red), those with C_{trough_1} <39 μg/mL (blue), and those with a C_{trough_1} ≥39 μg/mL (green) (developmental cohort). (D) Cumulative incidence of GR2-4 aGVHD for patients receiving placebo (red), those with C_{trough_1} <39 μg/mL (blue), and those with a C_{trough_1} ≥39 μg/mL (green) (validation cohort). The number of patients at risk are listed below the graph. Cumulative incidence plots represent unadjusted estimates, whereas the HR estimates are adjusted for the graft type.