Drug Interaction Report

ADJUST DOSE: Coadministration with potent inhibitors of CYP450 3A4 may significantly increase the plasma concentrations of pimavanserin, which is primarily metabolized by the isoenzyme. According to the product labeling, pimavanserin peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 1.5- and 3-fold, respectively, when given with the potent CYP450 3A4 inhibitor ketoconazole. High plasma levels of pimavanserin may increase the risk of QT interval prolongation, which has been associated with ventricular arrhythmias including torsade de pointes and sudden death.

MANAGEMENT: Pimavanserin dosage should be reduced to 10 mg once a day when used with potent CYP450 3A4 inhibitors.

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.