SLCO1B1

SLCO1B1 (solute carrier organic anion transporter family member 1B1) is a drug transporter that helps the body get rid of certain medicines through the liver. There are many medications that may be affected by  SLCO1B1.

There are many variations or genetic differences in the gene for SLCO1B1. These differences in the SLCO1B1 gene can lead to the production of a transport protein that that does not function normally to help the body get rid of drugs. A system designed to classify patients into 3 genotype categories based on the function of SLCO1B1 is used by clinicians to help guide drug therapy decisions.

Priority genotypes

Poor function – These patients have little or no SLCO1B1 transporter function. About 2 in 20 people have this genotype. 

• Drugs we recommend to avoid: 
  
  • Simvastatin. Blood levels of simvastatin are expected to be high in these patients and side effects, particularly muscle aches, are likely. Another medicine not affected by SLCO1B1 may be preferred. 
    
  • Other drugs may be affected. The PG4KDS study will evaluate what should be done for the dosing of these other drugs.
    

Decreased function – These patients have decreased SLCO1B1 transporter function compared to patients with normal SLCO1B1 function. About 2 in 10 people have this genotype. 

• Drugs we recommend to avoid: 
  
  • Simvastatin: Blood levels may be high in these patients and they may have simvastatin-associated muscle aches. 
    
  • Other drugs may be affected. The PG4KDS study will evaluate what should be done for the dosing of these other drugs.

Routine genotypes

We do not routinely adjust medicine doses based on the following genotypes, except in rare instances:

Normal function – These subjects have normal SLCO1B1 function. About 7 in 10 people have this genotype.

Legal Disclaimer: This page is intended to provide implementers with guidance on establishing a clinical pharmacogenetic program at their institution. Information contained on this page is for information and educational purposes only. Although reasonable efforts have been made to ensure that the information provided on this page is current, complete and, where appropriate, based on scientific evidence, St. Jude Children's Research Hospital makes no assurances as to whether the provided information will at all times be current or complete. St. Jude Children's Research Hospital, in offering this document, is not providing medical advice or offering a consultative opinion, and is not establishing a treatment relationship with any given individual. You, therefore, should not substitute information contained herein for your own professional judgment, nor should you rely on information provided herein in rendering a diagnosis or choosing a course of treatment for a particular individual.