Drug Interaction Report

GENERALLY AVOID: Coadministration with inhibitors of the organic anion transporting polypeptide (OATP) 1B3 hepatic uptake transporter and/or the hepatic bile acid uptake transporter sodium taurocholate co-transporting polypeptide (NTCP) may significantly increase the plasma concentrations and effects of zavegepant, which is a substrate of these transporters. When single-dose oral zavegepant (100 mg) was administered with the OATP 1B3 and NTCP inhibitor and strong CYP450 3A4 inducer, rifampin, at steady state, zavegepant peak plasma concentration (Cmax) and systemic exposure (AUC) increased by approximately 2.2- and 2.3-fold, respectively.

MANAGEMENT: Concomitant use of zavegepant with OATP 1B3 and/or NTCP inhibitors should generally be avoided.

ADJUST DOSING INTERVAL: Food may reduce the systemic bioavailability of amprenavir from fosamprenavir oral suspension. The mechanism of interaction has not been described. According to the product labeling, administration of fosamprenavir oral suspension (1400 mg single dose) with a high-fat meal (967 kcal, 67 g fat, 33 g protein, 58 g carbohydrate) reduced amprenavir peak plasma concentration (Cmax) by 46% and systemic exposure (AUC) by 28% compared to administration in a fasted state. The time to reach peak plasma level (Tmax) was delayed by 0.72 hours. In contrast, the same high-fat meal did not affect the pharmacokinetics of amprenavir from fosamprenavir tablets.

MANAGEMENT: Fosamprenavir suspension should be administered on an empty stomach in adults, but with food in pediatric patients to aid palatability and compliance. If emesis occurs within 30 minutes after dosing the suspension, the dose should be repeated. Fosamprenavir tablets may be taken with or without food.