Drug Interaction Report

GENERALLY AVOID: Coadministration with capmatinib may increase the plasma concentrations and risk of adverse effects of drugs that are substrates of P-glycoprotein (P-gp) and/or breast cancer resistance protein (BCRP) transporters, such as digoxin and rosuvastatin. The proposed mechanism is decreased clearance due to capmatinib-mediated inhibition of intestinal P-gp and/or BCRP efflux transport proteins. Coadministration with capmatinib increased the systemic exposure (AUC0-INF) and peak plasma concentration (Cmax) of digoxin (a P-gp substrate) by 47% and 74%, respectively. Concomitant use of capmatinib increased the AUC0-INF and Cmax of rosuvastatin (a BCRP substrate) by 108% and 204%, respectively.

MANAGEMENT: Coadministration of capmatinib with drugs that are substrates of P-gp and/or BCRP should generally be avoided. However, if concomitant use is unavoidable, caution is advised, particularly with drugs that have a narrow therapeutic range. Clinical and laboratory monitoring should be considered whenever capmatinib is added to or withdrawn from therapy with these drugs, and dosages adjusted as necessary. Patients should be monitored for the development of adverse effects.

Administration of digoxin with a high-fiber meal has been shown to decrease its bioavailability by almost 20%. Fiber can sequester up to 45% of the drug when given orally. Patients should be advised to maintain a regular diet without significant fluctuation in fiber intake while digoxin is being titrated.

Grapefruit juice may modestly increase the plasma concentrations of digoxin. The mechanism is increased absorption of digoxin due to mild inhibition of intestinal P-glycoprotein by certain compounds present in grapefruits. In 12 healthy volunteers, administration of grapefruit juice with and 30 minutes before, as well as 3.5, 7.5, and 11.5 hours after a single digoxin dose (0.5 mg) increased the mean area under the plasma concentration-time curve (AUC) of digoxin by just 9% compared to administration with water. Moreover, P-glycoprotein genetic polymorphism does not appear to influence the magnitude of the effects of grapefruit juice on digoxin. Thus, the interaction is unlikely to be of clinical significance.