Drug Interaction Report

GENERALLY AVOID: Coadministration with vimseltinib may increase the plasma concentrations of drugs that are substrates of the P-glycoprotein (P-gp) efflux transporter. The proposed mechanism, based on in vitro data, involves decreased clearance due to inhibition of P-gp by vimseltinib. Based on model-informed drug interaction studies, coadministration of the P-gp substrate dabigatran with vimseltinib (30 mg twice weekly) is predicted to increase the systemic exposure (AUC) and peak plasma concentration (Cmax) of dabigatran by 2 to 3-fold. However, if dabigatran is administered 4 hours after vimseltinib (30 mg twice weekly), the AUC and Cmax are predicted to increase by only up to 1.3-fold. Clinical data are not available.

MANAGEMENT: Concomitant use of vimseltinib with P-gp substrates should generally be avoided. If coadministration is considered necessary, vimseltinib should be taken at least 4 hours prior to the P-gp substrate. The individual product labeling of the P-gp substrate should be consulted for further guidance.

ADJUST DOSING INTERVAL: Administration with food may modestly affect the bioavailability of ritonavir from the various available formulations. When the oral solution was given under nonfasting conditions, peak ritonavir concentrations decreased 23% and the extent of absorption decreased 7% relative to fasting conditions. Dilution of the oral solution (within one hour of dosing) with 240 mL of chocolate milk or a nutritional supplement (Advera or Ensure) did not significantly affect the extent and rate of ritonavir absorption. When a single 100 mg dose of the tablet was administered with a high-fat meal (907 kcal; 52% fat, 15% protein, 33% carbohydrates), approximately 20% decreases in mean peak concentration (Cmax) and systemic exposure (AUC) were observed relative to administration after fasting. Similar decreases in Cmax and AUC were reported when the tablet was administered with a moderate-fat meal. In contrast, the extent of absorption of ritonavir from the soft gelatin capsule formulation was 13% higher when administered with a meal (615 KCal; 14.5% fat, 9% protein, and 76% carbohydrate) relative to fasting.

MANAGEMENT: Ritonavir should be taken with meals to enhance gastrointestinal tolerability.