Drug Interaction Report

MONITOR: Coadministration with niraparib may increase the plasma concentrations of drugs that are substrates of the breast cancer resistance protein (BCRP) transporter. The proposed mechanism is BCRP inhibition by niraparib. In vitro studies have shown that niraparib is able to inhibit BCRP, but a clinically meaningful interaction is unlikely.

MANAGEMENT: Caution is recommended if niraparib is used in combination with substrates of the breast cancer resistance protein (BCRP) transporter such as irinotecan, rosuvastatin, simvastatin, atorvastatin, and/or methotrexate. Monitoring for signs and symptoms of increased exposure to the BCRP substrate should be considered whenever niraparib is added to or withdrawn from therapy.

Food enhances the oral absorption and bioavailability of tenofovir, the active entity of tenofovir disoproxil fumarate. According to the product labeling, administration of the drug following a high-fat meal increased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of tenofovir by approximately 14% and 40%, respectively, compared to administration in the fasting state. However, administration with a light meal did not significantly affect the pharmacokinetics of tenofovir compared to administration in the fasting state. Food delays the time to reach tenofovir Cmax by approximately 1 hour. Tenofovir disoproxil fumarate may be administered without regard to meals.