Ivermectin Interacts With Human ABCG2

Ivermectin is an antiparasitic drug frequently administered to humans. It has a limited brain exposure that is attributed to the efflux activity of ABCB1/Abcb1. ABCG2/Abcg2 is also a major transporter present in most pharmacologically important barriers. However, interaction of ivermectin with Abcg2 shows species specificity and in many studies was confounded by the masking effect of ABCB1/Abcb1. In this study using cellular and membrane assays we show that ivermectin displays a high-affinity interaction with human ABCG2 with IC50 values in the 1-1.5 mu M range. This interaction may have implications in human ABCG2-mediated drug-drug interactions of ivermectin. (C) 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:94-97, 2011