EFS for the T-cell ALL/LL cohorts. Kaplan-Meier estimates of EFS, defined as the time from the date of first study drug administration to the first documented treatment failure, date of relapse from CR (ie, reappearance of leukemia blasts in the peripheral blood or >5% bone marrow blasts, reappearance of extramedullary disease, or new extramedullary disease), or death due to any cause, whichever occurs first. Median EFS for pooled children and young adults with T-cell ALL was 9.5 months (90% CI, 5.3-20.5). CI, confidence interval; NE, not evaluable.