Coadministration of Rifampin Significantly Reduces Odanacatib Concentrations in Healthy Subjects

详细信息    查看全文

• 作者：S. Aubrey Stoch ; Jeanine Ballard ; Christopher Gibson ; Filippos Kesisoglou ; Rose Witter ; Kelem Kassahun ; Stefan Zajic ; Anish Mehta ; Christine Brandquist ; Cynthia Dempsey ; Daria Stypinski and Marc L. Reitman
• 刊名：The Journal of Clinical Pharmacology
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：57
• 期：1
• 页码：110-117
• 全文大小：353K
• ISSN：1552-4604

文摘

This open-label 2-period study assessed the effect of multiple-dose administration of rifampin, a strong cytochrome P450 3A (CYP3A) and P-glycoprotein inducer, on the pharmacokinetics of odanacatib, a cathepsin K inhibitor. In period 1, 12 healthy male subjects (mean age, 30 years) received a single dose of odanacatib 50 mg on day 1, followed by a 28-day washout. In period 2, subjects received rifampin 600 mg/day for 28 days; odanacatib 50 mg was coadministered on day 14. Blood samples for odanacatib pharmacokinetics were collected at predose and on day 1 of period 1 and day 14 of period 2. Coadministration of odanacatib and rifampin significantly reduced odanacatib exposure. The odanacatib AUCb>0–∞b> geometric mean ratio (90% confidence interval) of odanacatib + rifampin/odanacatib alone was 0.13 (0.11–0.16). The harmonic mean ± jackknife standard deviation apparent terminal half-life (tb>½b>) was 71.6 ± 10.2 hours for odanacatib alone and 16.0 ± 3.4 hours for odanacatib + rifampin, indicating greater odanacatib clearance following coadministration with rifampin. Samples were collected in period 2 during rifampin dosing (days 1, 14, and 28) and after rifampin discontinuation (days 35, 42, and 56) to evaluate the ratio of plasma 4β-hydroxycholesterol to total serum cholesterol as a CYP3A4 induction biomarker; the ratio increased ∼5-fold over 28 days of daily dosing with 600 mg rifampin, demonstrating sensitivity to CYP3A4 induction.