Drug Interaction Report

MONITOR: Coadministration with inducers of CYP450 3A4 may decrease the plasma concentrations of the hepatitis C virus (HCV) NS3/4A protease inhibitors, boceprevir and telaprevir, which are metabolized by the isoenzyme. In 16 study subjects, administration of a single 750 mg dose of telaprevir during treatment with the potent CYP450 3A4 inducer rifampin (600 mg daily for 7 days) reduced the telaprevir peak plasma concentration (Cmax) and systemic exposure (AUC) by an average of 86% and 92%, respectively, compared to administration alone. No data are available for boceprevir; however, a similar interaction is expected.

MANAGEMENT: Caution is recommended if boceprevir or telaprevir is used in combination with a CYP450 3A4 inducer. Close clinical monitoring of the virologic response to the HCV NS3/4A protease inhibitor is recommended.

ADJUST DOSING INTERVAL: Food significantly enhances the oral bioavailability of boceprevir. When given at 800 mg three times daily with food, boceprevir exposure increased by up to 65% relative to administration in the fasting state. The bioavailability of boceprevir was similar regardless of meal type (e.g., high-fat versus low-fat) or whether taken 5 minutes prior to eating, during a meal, or immediately following completion of the meal. Therefore, boceprevir may be taken without regard to either meal type or timing of the meal.

MANAGEMENT: To ensure maximal oral absorption, boceprevir should be administered with a meal or light snack.