Solute carrier organic anion transporter family member 1B1 and 1B3 (OATP1B1/3)

Solute carrier organic anion transporter family member 1B1 (OATP1B1) and 1B3 (OATP1B3) are key hepatic uptake transporters located on the sinusoidal membrane of hepatocytes (UniProt P46721, Q9NPD5). They facilitate the entry of various endogenous substances, such as bilirubin and bile acids, and numerous drugs, including statins and certain antibiotics, into the liver for clearance (PubMed: 23143598). Because they are major determinants of drug exposure, OATP1B1 and OATP1B3 are frequent sites of clinically significant drug-drug interactions (DDIs). Inhibition of these transporters can lead to increased plasma concentrations of substrate drugs, potentially causing adverse effects like statin-associated muscle symptoms or rhabdomyolysis (FDA Guidance). Genetic variants, particularly in the SLCO1B1 gene, significantly influence transporter activity and are associated with altered drug safety and efficacy profiles (CPIC Guidelines). Endogenous biomarkers, such as coproporphyrin I, are increasingly utilized in clinical research to monitor OATP1B1/3 activity and predict DDI risk (PubMed: 29156134). These transporters are also involved in the hepatic uptake of imaging agents and certain toxins. Their expression is often altered in liver diseases, which can further impact drug disposition. Overall, OATP1B1 and OATP1B3 are critical components of the hepatic detoxification system and essential considerations in drug development.

Other names

SLCO1B1SLCO1B3OATP1B1OATP1B3OATP-COATP-8LST-1LST-2OATP2OATP-H

Facilitated diffusion of organic anions into hepatocytes; drugs can act as substrates or inhibitors (competitive or non-competitive).