Organic anion transporting polypeptide 1B1 and Organic anion transporting polypeptide 1B3 (OATP1B1 and OATP1B3)

Organic anion transporting polypeptides 1B1 (OATP1B1) and 1B3 (OATP1B3) are membrane transporters of the solute carrier organic anion transporter family, primarily expressed in the liver on the basolateral membrane of hepatocytes[4][6][7][8]. They facilitate the sodium-independent uptake of a diverse range of endogenous substances (such as bilirubin, bile acids, steroid conjugates, thyroid hormones) and drugs (including statins, anticancer agents, and antibiotics) from the blood into the liver, enabling their subsequent metabolism and biliary excretion[3][4][6]. Polymorphisms in these transporters can lead to reduced drug clearance and cause adverse drug reactions, including potentially severe interactions with statins (e.g., myopathy)[4][6][7][8]. Both the U.S. FDA and EMA require evaluation of potential drug–drug interactions involving these transporters during drug development due to their critical role in pharmacokinetics[6][7].

Other names

SLCO1B1SLCO1B3SLC21A6 (for OATP1B1)OATP-COATPCLST-1LST1HBLRR

Substrate for hepatic uptake (for most drugs; enables liver clearance). Inhibition (drugs may compete for or inhibit transporter function, leading to altered drug exposure).