Plasma Concentrations of Venetoclax and Pharmacogenetics Correlated with Drug Efficacy in Treatment Naive Leukemia Patients: a Retrospective Study

Venetoclax (VEN) was the only Bcl-2 inhibitor approved yet and showed large differences in clinical efficacy. The aim of the study was to explore the relationships between the plasma concentration and efficacy of VEN, and identify potential influencing factors. A retrospective cohort study was conducted and a total of 76 trough (C) and 91 6 h post-dose plasma concentration (C) blood concentrations of VEN were collected in 54 patients. C/D concentration of VEN was found to be significantly correlated with treatment efficacy (p = 0.006) in leukemia patients with good or intermediate prognosis stratification. A ROC curve was then established and the cut-off value was calculated as 0.2868 μg/ml (AUC = 0.7097, p = 0.1081). Besides, patients co-administered with triazoles or carrying CYP3A5 rs776746 AA/AG genotypes were prone to induce higher VEN plasma concentration regardless of whether VEN dosage was reduced or not. Through LASSO-logistic regression and nomogram analysis, chemotherapy regimens and neutrophil percentages were identified as the critical elements that may predict drug response. Above all, in addition to identify prognostic stratification, AML patients taken with VEN were suggested to test plasma concentration routinely so as to achieve desired efficacy, especially when co-administered with triazoles or carried with CYP3A5 rs776746 AA/AG.