PT - JOURNAL ARTICLE AU - Li, Xiuli AU - Zhong, Kan AU - Guo, Zitao AU - Zhong, Dafang AU - Chen, Xiaoyan TI - Fasiglifam (TAK-875) Inhibits Hepatobiliary Transporters: A Possible Factor Contributing to Fasiglifam-Induced Liver Injury AID - 10.1124/dmd.115.064121 DP - 2015 Nov 01 TA - Drug Metabolism and Disposition PG - 1751--1759 VI - 43 IP - 11 4099 - http://dmd.aspetjournals.org/content/43/11/1751.short 4100 - http://dmd.aspetjournals.org/content/43/11/1751.full SO - Drug Metab Dispos2015 Nov 01; 43 AB - Fasiglifam (TAK-875), a selective G-protein–coupled receptor 40 agonist, was developed for the treatment of type 2 diabetes mellitus; however, its development was terminated in phase III clinical trials because of liver safety concerns. Our preliminary study indicated that intravenous administration of 100 mg/kg of TAK-875 increased the serum total bile acid concentration by 3 to 4 times and total bilirubin levels by 1.5 to 2.6 times in rats. In the present study, we examined the inhibitory effects of TAK-875 on hepatobiliary transporters to explore the mechanisms underlying its hepatotoxicity. TAK-875 decreased the biliary excretion index and the in vitro biliary clearance of d8-taurocholic acid in sandwich-cultured rat hepatocytes, suggesting that TAK-875 impaired biliary excretion of bile acids, possibly by inhibiting bile salt export pump (Bsep). TAK-875 inhibited the efflux transporter multidrug resistance-associated protein 2 (Mrp2) in rat hepatocytes using 5 (and 6)-carboxy-2′,7′-dichlorofluorescein as a substrate. Inhibition of MRP2 was further confirmed by reduced transport of vinblastine in Madin-Darby canine kidney cells overexpressing MRP2 with IC50 values of 2.41 μM. TAK-875 also inhibited the major bile acid uptake transporter Na+/taurocholate cotransporting polypeptide (Ntcp), which transports d8-taurocholic acid into rat hepatocytes, with an IC50 value of 10.9 μM. TAK-875 significantly inhibited atorvastatin uptake in organic anion transporter protein (OATP) 1B1 and OATP1B3 cells with IC50 values of 2.28 and 3.98 μM, respectively. These results indicate that TAK-875 inhibited the efflux transporter MRP2/Mrp2 and uptake transporters Ntcp and OATP/Oatp, which may affect bile acid and bilirubin homeostasis, resulting in hyperbilirubinemia and cholestatic hepatotoxicity.