8.C.3 The Bilastine (Bilastine) Family
Bilastine is a nonsedating H(1) antihistamine for the treatment of allergic rhinoconjunctivitis and urticaria. Its in vitro inhibitory effects were assessed on 12 human transporters: four efflux pumps [multidrug resistance protein 1 (MDR1) or P-glycoprotein, breast cancer resistance protein (BCRP), multidrug resistance associated protein 2 (MRP2), and the bile salt export pump) and eight uptake transporters (sodium taurocholate cotransporting polypeptide, organic cation transporter (OCT)1, organic anion transporter OAT1, OAT3, OCT2, OATP2B1, OATP1B1, and OATP1B3) (Lucero et al., 2012). Only mild inhibition was found for MDR1-, OCT1-, and OATP2B1-mediated transport at the highest bilastine concentration assayed (300 μM; half-maximal inhibitory concentration: ≥300 μM). Of MDR1, BCRP, OAT1, OAT3, and OCT2, only MDR1 active transport of bilastine was relevant. It did not appear to be a substrate of OCT2, OAT1, or OAT3; nor was it transported substantially by BCRP. Consequently, bilastine is not an inhibitor of these transporters.