Venetoclax has been approved in the United States, Europe, Canada, and Australia for appropriate patients with difficult-to-treat chronic lymphocytic leukemia (CLL). The objective of this phase 1 study was to evaluate the pharmacokinetics of venetoclax in Chinese subjects to inform the dose selection of venetoclax in a phase 2 study of patients with relapsed/refractory (R/R) CLL in China. Twelve healthy first-generation Han Chinese subjects received a single 100-mg dose of venetoclax following a low-fat breakfast. Pharmacokinetic parameters were estimated using noncompartmental methods. After a single dose of venetoclax in healthy Chinese subjects, the median time to peak concentration was 6 hours (range, 4 to 6 hours), and the mean +/- SD C-max, AUC(inf), and terminal half-life were 1.0 +/- 0.32 mu g/mL, 12.6 +/- 5.4 mu g.h/mL, and 18.4 +/- 2.97 hours, respectively. On average, venetoclax C-max and AUC(inf) values were 94% and 66% higher, respectively, in Chinese subjects compared with those observed historically for non-Asian subjects receiving the same dose. Based on these pharmacokinetic results and the established exposure-response relationship of venetoclax in non-Asian CLL subjects, a 400-mg once-daily dosage regimen was selected for evaluating the venetoclax pharmacokinetics, efficacy, and safety in the venetoclax phase 2 open-label study in Chinese subjects with R/R CLL.