There was a trend for low treosulfan AUC(0–∞) to be associated with rejection (hazard ratio (HR) (95% confidence interval (CI)) = 0.08 (0, 1.37); P = 0.08); four covariates were significant by association with 1-year mortality (GSTA1, NQO1 polymorphisms, incidence of acute GVHD and hepatic SOS (Table S3)). Here, NQO1 is linked to acute graft versus host disease.