Drug Interaction Report

MONITOR: Coadministration with resmetirom may increase the plasma concentrations and effects of drugs that are substrates of hepatic uptake transporters organic anion transporting polypeptides (OATP) 1B1, OATP 1B3, and/or the intestinal and hepatobiliary efflux transporter breast cancer resistance protein (BCRP). Resmetirom is both a substrate and an inhibitor of these transporters. Clinical studies exist for resmetirom with OATP1B1 and OATP1B3 substrates, simvastatin, and pravastatin; as well as with rosuvastatin and atorvastatin which are BCRP, OATP1B1 and OATP1B3 substrates. Resmetirom was shown to increase the systemic exposure (AUC) of simvastatin, pravastatin, rosuvastatin, and atorvastatin by 1.7-fold, 1.4-fold, 1.8-fold, and 1.4-fold, respectively. Clinical data are not available for other OATP 1B1, OATP 1B3 and/or BCRP substrates.

MANAGEMENT: Caution and closer monitoring may be advised if resmetirom is coadministered with drugs that are substrates of the OATP 1B1, OATP 1B3, and/or BCRP transporters. Dosage adjustments as well as clinical and laboratory monitoring for the development of adverse effects may be appropriate for some drugs whenever resmetirom is added to or withdrawn from therapy. Individual product labeling should be consulted for further guidance.

ADJUST DOSING INTERVAL: Food may reduce the oral bioavailability of afatinib. According to the product labeling, administration of afatinib with a high-fat meal decreased peak plasma concentration (Cmax) by 50% and systemic exposure (AUC) by 39% compared to administration in the fasted state.

MANAGEMENT: Afatinib should be taken at least 1 hour before or 2 hours after a meal.