Effect of Antacids and Ranitidine on the Single-Dose Pharmacokinetics of Fosamprenavir

Abstract

ABSTRACT Single doses of MAALOX TC and ranitidine were administered separately with 1,400 mg of fosamprenavir (FPV). MAALOX TC decreased the area under the concentration-time curve from 0 to 24 h (AUC 0-24 ) for plasma amprenavir (APV) by 18% and the maximum concentration of drug in serum ( C max ) by 35%; the plasma APV concentration at 12 h ( C 12 ) increased by 14%. Ranitidine at 300 mg decreased the AUC 0-24 for plasma APV by 30% and C max by 51%; C 12 was unchanged. FPV may be coadministered with antacids without concern and without separation in dosing; however, caution is recommended when FPV is coadministered with histamine 2 - receptor antagonists or proton pump inhibitors.