SLCO1B1 and ABCB1 Variants Synergistically Influence the Atorvastatin Treatment Response in South Indian Coronary Artery Disease Patients

Introduction: Atorvastatin exhibits wide interindividual variability in treatment response, limiting the drug efficacy in coronary artery disease patients. Aim: To study the effect of genetic variants involved in atorvastatin transport/metabolism and correlate their lipid-lowering efficacy. Materials & methods: Genotyping was performed using 5'-hydrolysis probe method (n = 412), and the study evaluated the treatment response in 86 patients. Results: Significant reduction in total cholesterol and low-density lipoprotein cholesterol (LDL-C) were observed in SLCO1B1-rs4149056, rs4363657 and ABCB1-rs1045642 genotypes. The combined genotypes of ABCB1 and SLCO1B1 showed a strong synergistic effect in reducing the total cholesterol and LDL-C. Diabetes and smoking were observed to influence the LDL-C reduction. Conclusion: The genetic variants of SLCO1B1 and ABCB1 predict the lipid-lowering efficacy of atorvastatin, and this may be useful in genotype-guided statin therapy for coronary artery disease patients.