Standard- vs High-Dose Clopidogrel Based on Platelet Function Testing After Percutaneous Coronary Intervention

Abstract

Current guidelines recommend treating patients undergoing percutaneous coronary intervention (PCI) and drug-eluting stent implantation with a combination of aspirin and P2Y₁₂ antagonist for at least 1 year.¹ Clopidogrel is a prodrug that requires biotransformation into an active metabolite in order to exert its inhibitory effect on platelet activation and aggregation.² Pharmacokinetic and pharmacodynamic studies have demonstrated wide interindividual variability in the concentration of active metabolite and in the magnitude of platelet inhibition achieved by recommended loading and maintenance doses of clopidogrel.^3-5 Although some of this variability is due to genetic polymorphisms that affect the functional activity of the CYP2C19 enzyme, most cannot be explained by genotype or other clinical characteristics.^6,7