ibution
Venetoclax is highly bound to human plasma protein with unbound fraction in plasma <0.01 across a concentration range of 1-30 µM (0.87-26 µg/mL). The mean blood-to-plasma ratio was 0.57. The population estimate for apparent volume of distribution (Vdss/F) of venetoclax ranged from 256-321 L in patients.
Elimination
The population estimate for the terminal elimination half-life of venetoclax was approximately 26 hours. The pharmacokinetics of venetoclax does not change over time.
Metabolism
In vitro studies demonstrated that venetoclax is predominantly metabolized by CYP3A4/5. M27 was identified as a major metabolite in plasma with an inhibitory activity against BCL-2 that is at least 58-fold lower than venetoclax in vitro.
Excretion
After single oral administration of 200 mg radiolabeled [14C]-venetoclax dose to healthy subjects, >99.9% of the dose was recovered in feces and <0.1% of the dose was excreted in urine within 9 days, indicating that hepatic elimination is responsible for the clearance of venetoclax from the systemic circulation. Unchanged venetoclax accounted for 20.8% of the administered radioactive dose excreted in feces.
Special Populations
Age, Race, Sex, and Weight
Based on population pharmacokinetic analyses, age, race, sex, and weight do not have a clinically meaningful effect on venetoclax clearance.
Renal Impairment
Based on a population pharmacokinetic analysis that included 211 subjects with mild renal impairment (CrCl ≥60 and <90 mL/min, calculated by Cockcroft-Gault equation), 83 subjects with moderate renal impairment (CrCl ≥30 and <60 mL/min) and 210 subjects with normal renal function (CrCl ≥90 mL/min), venetoclax exposures in subjects with mild or moderate renal impairment are similar to those with normal renal function. The pharmacokinetics of venetoclax has not been studied in subjects with severe renal impairment (CrCl <30 mL/min) or subjects on dialysis [see Use in Specific Populations (8.6)].
Hepatic Impairment
Based on a population pharmacokinetic analysis that included 69 subjects with mild hepatic impairment, 7 subjects with moderate hepatic impairment and 429 subjects with normal hepatic function, venetoclax exposures are similar in subjects with mild and moderate hepatic impairment and normal hepatic function. The NCI Organ Dysfunction Working Group criteria for hepatic impairment were used in the analysis. Mild hepatic impairment was defined as normal total bilirubin and aspartate transaminase (AST) > upper limit of normal (ULN) or total bilirubin >1.0 to 1.5 times ULN, moderate hepatic impairment as total bilirubin >1.5 to 3.0 times ULN, and severe hepatic impairment as total bilirubin >3.0 times ULN. The pharmacokinetics of venetoclax has not been studied in subjects with severe hepatic impairment [see Use in Specific Populations (8.7)].
Drug Interactions
Ketoconazole
Co-administration of 400 mg once daily ketoconazole, a strong CYP3A, P-gp and BCRP inhibitor, for 7 days in 11 previously treated NHL patients increased venetoclax Cmax by 2.3-fold and AUC∞ by 6.4-fold [see Drug Interactions (7.1)].
Rifampin multiple doses
Co-administration of 600 mg once daily rifampin, a strong CYP3A inducer, for 13 days in 10 healthy subjects decreased venetoclax Cmax by 42% and AUC∞ by 71% [see Drug Interactions (7.1)].
Rifampin single dose
Co-administration of a 600 mg single dose of rifampin, an OATP |
