Drug Interactions between baloxavir marboxil and Neo-Forte

ADJUST DOSING INTERVAL: Concomitant use of some oral medications may reduce the bioavailability of orally administered iron, and vice versa.

Food taken in conjunction with oral iron supplements may reduce the bioavailability of the iron. However, in many patients intolerable gastrointestinal side effects occur necessitating administration with food.

MANAGEMENT: Ideally, iron products should be taken on an empty stomach (i.e., at least 1 hour before or 2 hours after meals), but if this is not possible, administer with meals and monitor the patient more closely for a subtherapeutic effect. Some studies suggest administration of iron with ascorbic acid may enhance bioavailability. In addition, administration of oral iron products and some oral medications should be separated whenever the bioavailability of either agent may be decreased. Consult the product labeling for specific separation times and monitor clinical responses as appropriate.

GENERALLY AVOID: Coadministration with foods or medications that contain polyvalent cations such as dairy products, calcium-fortified beverages, certain laxatives, antacids, or oral supplements may decrease the plasma concentrations and therapeutic efficacy of baloxavir. The proposed mechanism is chelation of baloxavir by polyvalent cations, forming a complex that is poorly absorbed from the gastrointestinal tract. A significant decrease in baloxavir exposure was observed in monkeys when the prodrug, baloxavir marboxil, was coadministered with calcium, aluminum, magnesium, or iron. However, clinical data in humans are lacking.

When baloxavir marboxil was administered with food, baloxavir peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 48% and 36%, respectively, relative to administration under fasting. These changes are not considered clinically significant.

MANAGEMENT: Baloxavir marboxil may be taken with or without food. However, coadministration with dairy products, calcium-fortified beverages, or polyvalent cation-containing laxatives, antacids, or oral supplements (e.g., calcium, iron, magnesium, selenium, or zinc) should be avoided.