Drug Interaction Report

CONTRAINDICATED: Coadministration with potent inhibitors of CYP450 3A4 may significantly increase the plasma concentrations of ticagrelor, which is primarily metabolized by the isoenzyme. In healthy volunteers, administration of ticagrelor in combination with the potent CYP450 3A4 inhibitor ketoconazole resulted in increased ticagrelor peak plasma concentration (Cmax) and systemic exposure (AUC) by 2.4-fold and 7.3-fold, respectively, and reduced Cmax and AUC of the active metabolite by 89% and 56%, respectively.

MANAGEMENT: Concomitant use of ticagrelor with potent CYP450 3A4 inhibitors is considered contraindicated by some foreign authorities. The U.S. labeling for ticagrelor recommends avoiding use with potent CYP450 3A4 inhibitors. Labeling for itraconazole, a potent CYP450 3A4 inhibitor, specifically contraindicates use with ticagrelor during and for 2 weeks after treatment with itraconazole.

ADJUST DOSING INTERVAL: Food reduces the oral absorption and bioavailability of voriconazole. According to the product labeling, administration of multiple doses of voriconazole with high-fat meals decreased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) by 34% and 24%, respectively, when the drug is administered as a tablet, and by 58% and 37%, respectively, when administered as the oral suspension.

MANAGEMENT: To ensure maximal oral absorption, voriconazole tablets and oral suspension should be taken at least one hour before or after a meal.