In vivo single-agent venetoclax responses of pediatric ALL xenografts. Responses of representative xenografts from the (A) MLLr-ALL, (B) BCP-ALL, (C) JAK-mutated ALL, (D) T-ALL, and (E) ETP-ALL subpanels treated with venetoclax (100 mg/kg for 21 days, dotted lines) or vehicle control (solid lines); results from individual mice are represented by gray lines, whereas the black lines summarize the outcome for each cohort. In each case, the left panels represent the %huCD45⁺ of individual mice over time, whereas the right panels show the proportion of mice remaining event free. (F) Leukemia growth delay (T − C) of ALL xenograft subtypes following treatment with navitoclax or venetoclax. Each data point represents the median cohort leukemia growth delay for each xenograft; the horizontal bar represents the median for each ALL subtype. Data from the navitoclax cohort have been published previously²⁷  and are included here for comparison. Statistical comparison between cohorts treated with navitoclax vs venetoclax was by unpaired Student t tests corrected for multiple comparisons using the Bonferroni method. (G) “COMPARE-like” plot of the difference between the median ORM of xenografts shown in Table 1 and the midpoint response (which corresponds to a score of 5). Bars to the right or left of the midpoint represent objective responses or nonobjective responses, respectively. Xenografts achieving a PR (median ORM 6), CR (median ORM 8), or MCR (median ORM 10) classify as responders, whereas those with progressive disease (PD1, median ORM 0; or PD2, median ORM 2) classify as nonresponders.