Kevin J Freise1, Beibei Hu1, Ahmed Hamed Salem2,3. 1. AbbVie Inc., 1 North Waukegan Road, North Chicago, IL, 60064, USA. 2. AbbVie Inc., 1 North Waukegan Road, North Chicago, IL, 60064, USA. ahmed.salem@abbvie.com. 3. Department of Clinical Pharmacy, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt. ahmed.salem@abbvie.com.
Abstract
PURPOSE: Venetoclax is a selective BCL-2 inhibitor indicated for the treatment of patients with chronic lymphocytic leukemia (CLL). It is predominately metabolized by cytochrome P450 (CYP) 3A. The study objective was to determine the effect of different dosage regimens of ritonavir, a strong CYP3A inhibitor, on the pharmacokinetics of venetoclax in 20 healthy subjects. METHODS: In cohorts 1 and 2, subjects received single 10 mg doses of venetoclax in periods 1 and 2 and a single 50- or 100-mg dose of ritonavir in period 2. In cohort 3, subjects received 10-mg venetoclax doses on day 1 of period 1 and days 1 and 11 of period 2, and 50 mg ritonavir daily on days 1 to 14 of period 2. RESULTS: Single doses of 50 and 100 mg ritonavir increased the venetoclax maximum concentration (Cmax) 2.3- to 2.4-fold compared to venetoclax alone and the area under the curve (AUC) 6.1- and 8.1-fold, respectively. Daily 50 mg ritonavir resulted in a 2.4- and 7.9-fold increase in venetoclax Cmax and AUC, respectively. Administration of 50 mg ritonavir daily saturated CYP3A inhibition and completely inhibited the formation of the major venetoclax metabolite M27. Time-dependent CYP3A inhibition with daily 50 mg ritonavir was offset by ritonavir CYP3A induction, resulting in a limited net increase in CYP3A inhibition with multiple doses. CONCLUSION: After completion of the dose ramp-up, venetoclax dose reductions of at least 75% are recommended when administered concomitantly with strong CYP3A inhibitors to maintain venetoclax exposures within the established therapeutic window for CLL treatment.
PURPOSE:Venetoclax is a selective BCL-2 inhibitor indicated for the treatment of patients with chronic lymphocytic leukemia (CLL). It is predominately metabolized by cytochrome P450 (CYP) 3A. The study objective was to determine the effect of different dosage regimens of ritonavir, a strong CYP3A inhibitor, on the pharmacokinetics of venetoclax in 20 healthy subjects. METHODS: In cohorts 1 and 2, subjects received single 10 mg doses of venetoclax in periods 1 and 2 and a single 50- or 100-mg dose of ritonavir in period 2. In cohort 3, subjects received 10-mg venetoclax doses on day 1 of period 1 and days 1 and 11 of period 2, and 50 mg ritonavir daily on days 1 to 14 of period 2. RESULTS: Single doses of 50 and 100 mg ritonavir increased the venetoclax maximum concentration (Cmax) 2.3- to 2.4-fold compared to venetoclax alone and the area under the curve (AUC) 6.1- and 8.1-fold, respectively. Daily 50 mg ritonavir resulted in a 2.4- and 7.9-fold increase in venetoclax Cmax and AUC, respectively. Administration of 50 mg ritonavir daily saturated CYP3A inhibition and completely inhibited the formation of the major venetoclax metabolite M27. Time-dependent CYP3A inhibition with daily 50 mg ritonavir was offset by ritonavirCYP3A induction, resulting in a limited net increase in CYP3A inhibition with multiple doses. CONCLUSION: After completion of the dose ramp-up, venetoclax dose reductions of at least 75% are recommended when administered concomitantly with strong CYP3A inhibitors to maintain venetoclax exposures within the established therapeutic window for CLL treatment.
Authors: Sumit Bhatnagar; Dwaipayan Mukherjee; Ahmed Hamed Salem; Dale Miles; Rajeev M Menon; John P Gibbs Journal: Cancer Chemother Pharmacol Date: 2021-01-04 Impact factor: 3.333