Giotrif Drug Interactions

P-glycoprotein (P-gp) interactions: Based on in vitro data, afatinib is a substrate of P-gp. Based on clinical data, concomitant administration of strong P-gp inhibitors or inducers may alter exposure to afatinib.
Results of a drug interaction trial demonstrated that Afatinib dimaleate (Giotrif) can be safely combined with P-gp inhibitors (such as ritonavir) as long as the inhibitor is administered simultaneously with or after Afatinib dimaleate (Giotrif). If administered prior to Afatinib dimaleate (Giotrif), strong P-gp inhibitors (including but not limited to ritonavir, cyclosporine A, ketoconazole, itraconazole, erythromycin, verapamil, quinidine, tacrolimus, nelfinavir, saquinavir, and amiodarone) may increase exposure to afatinib and should be used with caution (see Dosage & Administration, Precautions and Pharmacology: Pharmacokinetics under Actions).
Strong P-gp inducers (including but not limited to rifampicin, carbamazepine, phenytoin, phenobarbital or St. John's Wort) may decrease exposure to afatinib (see Precautions and Pharmacology: Pharmacokinetics under Actions).
Food effect on afatinib: Co-administration of a high-fat meal with Afatinib dimaleate (Giotrif) resulted in a significant decrease of exposure to afatinib by about 50% in regard to C_max and 39% in regard to AUC_0-∞. Afatinib dimaleate (Giotrif) should be administered without food (see Dosage & Administration and Pharmacology: Pharmacokinetics under Actions).