Clopidogrel pharmacogenomics and risk of inadequate platelet inhibition: US FDA recommendations

Antiplatelet therapy with clopidogrel is the current standard of care for coronary artery disease patients undergoing a percutaneous coronary intervention. However, approximately 25% of patients experience a subtherapeutic antiplatelet response. Clopidogrel is a prodrug that undergoes hepatic biotransformation by CYP2C19 into its active metabolite. Several studies have reported that, compared with wild-type individuals, CYP2C19 variant allele carriers exhibit a significantly lower capacity to metabolize clopidogrel into its active metabolite and inhibit platelet activation, and are therefore at significantly higher risk of adverse cardiovascular events. Consequently, the US FDA has recently changed clopidogrel's prescribing information to highlight the impact of CYP2C19 genotype on clopidogrel pharmacokinetics, pharmacodynamics and clinical response. Future studies remain necessary to develop effective personalized therapeutic strategies for CYP2C19 variant allele carriers and other individuals at risk for clopidogrel non responsiveness.