Drug Interaction Report

MONITOR: Coadministration with inhibitors of P-glycoprotein (P-gp), uridine diphosphate glucuronosyltransferase (UGT) 1A1 or 2B7, and/or breast cancer resistance protein (BCRP) may increase the plasma levels and risk of adverse effects of binimetinib. The proposed mechanism involves the reduced metabolic clearance of binimetinib through inhibition of P-gp, UGT 1A1, UGT 2B7, and/or BCRP. The clinical significance of this interaction is unknown as no clinically relevant drug interactions have been demonstrated with binimetinib.

MANAGEMENT: Until further information is available, caution is recommended if binimetinib must be used concomitantly with P-gp, UGT 1A1, UGT 2B7, and/or BCRP inhibitors. Binimetinib should be monitored more closely whenever a P-gp, UGT 1A1, UGT 2B7, and/or BCRP inhibitor is added to or withdrawn from therapy, and the binimetinib dosage adjusted as necessary.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of crizotinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. Because crizotinib is associated with concentration-dependent prolongation of the QT interval, increased levels may potentiate the risk of ventricular arrhythmias such as torsade de pointes and sudden death.

Food has no significant effect on the gastrointestinal absorption of crizotinib. According to the product labeling, a high-fat meal reduced crizotinib peak plasma concentration (Cmax) and systemic exposure (AUC) by approximately 14%.

MANAGEMENT: Patients treated with crizotinib should avoid consumption of grapefruit, grapefruit juice, and any supplement containing grapefruit extract. Crizotinib may be taken without regards to food.

The recommended maximum number of medicines in the 'multikinase inhibitors' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'multikinase inhibitors' category:

• binimetinib
• crizotinib

Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.