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Pharmacogenetics of clopidogrel
Stephen A O'Connor1, Jean-Sebastien Hulot, Johanne Silvain
1Institut de Cardiologie, INSERM U 937, Groupe A.C.T.I.O.N. Groupe Hospitalier Pitié-Salpêtrière, 47, boulevard de l'Hôpital, 75013 Paris, France.
Current Pharmaceutical Design
|June 26, 2012
Summary
Genetic factors influence clopidogrel effectiveness, leading to variable patient responses. Identifying specific gene variants may personalize treatment for acute coronary syndrome patients, improving outcomes.
Area of Science:
- Pharmacogenomics
- Cardiovascular Medicine
- Drug Metabolism
Background:
- Clopidogrel and aspirin are crucial for acute coronary syndrome (ACS) and percutaneous coronary intervention (PCI) patients.
- Variable patient responses to clopidogrel, due to genetic factors, result in high on-treatment platelet reactivity (HPR) and increased ischemic events.
- Hepatic cytochrome P450 (CYP)-dependent metabolism is key to clopidogrel's efficacy.
Purpose of the Study:
- To investigate the role of genetic variability, specifically CYP 2C19 loss-of-function alleles, in clopidogrel response.
- To explore the clinical implications of identifying patients with HPR due to genetic factors.
- To assess the potential of genotype-guided therapy in ACS patients.
Main Methods:
- Review of pharmacogenomic studies analyzing CYP 2C19 variants and their association with clopidogrel metabolism.
- Analysis of data linking genetic profiles to active metabolite levels, platelet inhibition, and clinical outcomes.
- Consideration of point-of-care genetic testing development and its clinical utility.
Main Results:
- The CYP 2C19*2 allele is a primary genetic determinant of reduced clopidogrel antiplatelet effect.
- Carriers of loss-of-function alleles exhibit lower active metabolite levels, increased platelet reactivity, and poorer cardiovascular outcomes.
- Current evidence suggests genetic testing is not yet recommended for routine clinical practice due to limited prospective data.
Conclusions:
- Genetic variability significantly impacts clopidogrel efficacy, contributing to treatment variability in ACS patients.
- While routine genetic testing is not advised, its combination with platelet function analysis may benefit select ACS patients undergoing stenting with risk factors.
- Further prospective research is needed to establish the definitive role of genotype-guided clopidogrel therapy.
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