Drug Interaction Report

MONITOR: Coadministration with CYP450 3A4 inducers and/or P-glycoprotein (P-gp) inducers may decrease the plasma concentrations of tepotinib. The proposed mechanism involves induction of CYP450 3A4, which is one of the primary enzymes responsible for the metabolic clearance of tepotinib, and induction of the efflux transporter P-gp, of which tepotinib is also a substrate. However, the effect of CYP450 3A4 inducers and/or P-gp inducers on tepotinib has not been studied clinically.

MANAGEMENT: The potential for diminished pharmacologic effects of tepotinib should be considered during coadministration with CYP450 3A4 inducers and/or P-gp inducers. Alternative treatments may be required if an interaction is suspected.

ADJUST DOSING INTERVAL: Food may enhance the oral bioavailability of bexarotene. In one clinical study, bexarotene peak plasma concentration (Cmax) and systemic exposure (AUC) resulting from a 75 to 300 mg dose were 35% and 48% higher, respectively, when administered after a fat-containing meal relative to a glucose solution. In all clinical trials, patients were instructed to take bexarotene with or immediately following a meal.

Coadministration with inhibitors of CYP450 3A4 such as grapefruit juice may theoretically increase the plasma concentrations of bexarotene. In vitro studies suggest that bexarotene is metabolized by CYP450 3A4. However, concomitant administration with multiple doses of ketoconazole, a potent CYP450 3A4 inhibitor, did not alter bexarotene plasma concentrations, which would imply that bexarotene elimination is not substantially dependent on CYP450 3A4 metabolism in vivo.

MANAGEMENT: Because safety and efficacy data are based upon administration with food, bexarotene should be administered once daily with a meal. Patients may want to avoid consuming large amounts of grapefruit or grapefruit juice.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of tepotinib. When tepotinib was administered after a high-fat, high-calorie meal (approximately 800 to 1000 calories; 150 calories from protein, 250 calories from carbohydrate, 500 to 600 calories from fat), tepotinib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 2-fold and 1.6-fold, respectively, compared to administration under fasted conditions.

MANAGEMENT: Tepotinib should be administered with food at approximately the same time each day.