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

OATP1B1 and OATP1B3 are liver-specific membrane transporters belonging to the organic anion transporting polypeptides (OATP) family within the solute carrier (SLC) superfamily[2][3][5]. These proteins mediate the sodium-independent uptake of a broad range of endogenous substances (such as bile acids, bilirubin, steroid and thyroid hormone conjugates) and exogenous compounds (including many drugs) into hepatocytes for metabolism and biliary excretion[2][3][5][9]. They play a key role in determining drug pharmacokinetics, and their function is impacted by genetic variants and drug-drug interactions[5][8][9]. Clinical inhibitors and substrates include several statins, cyclosporine, gemfibrozil, repaglinide, methotrexate, and various antibiotics and antivirals[3][5][4]. Alterations in their activity, due to pharmacological inhibition or genetic variation, can cause significant safety concerns (such as statin-induced rhabdomyolysis) and necessitate adjustments in drug dosing[3][8][5]. Both OATP1B1 and OATP1B3 are recommended targets for regulatory evaluation in drug development due to their clinical relevance in drug disposition and the potential for drug-drug interactions[2][5][8].

Other names

SLCO1B1 (gene name for OATP1B1)SLCO1B3 (gene name for OATP1B3)HBLRR (OATP1B1)LST-1 (OATP1B1)LST1 (OATP1B1)OATP-C (OATP1B1)OATP2 (OATP1B1)OATPC (OATP1B1)SLC21A6 (OATP1B1)LST-2 (OATP1B3)OATP8 (OATP1B3)SLC21A8 (OATP1B3)

Substrate for hepatic uptake via OATP1B1/OATP1B3 Inhibition (drugs or genetic variants block OATP1B1/OATP1B3 function, resulting in increased plasma concentration of substrates) Modulation of transporter expression or function (polymorphism or drug interaction alters transporter activity)