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Published on: April 1, 2019
Genetic testing for CYP450 polymorphisms to predict response to clopidogrel: current evidence and test availability.
1Office of Public Health Genomics, Centers for Disease Control and Prevention.
Plos Currents
|September 30, 2010
Summary
Genetic testing for CYP2C19 variants can identify patients unresponsive to clopidogrel, a common anti-platelet drug. This allows for alternative treatments, reducing risks of heart attack and stroke.
Area of Science:
- Pharmacogenomics
- Cardiovascular Medicine
- Clinical Chemistry
Background:
- Clopidogrel bisulfate is a widely prescribed anti-platelet medication for preventing blood clots in various cardiovascular conditions.
- Patient response to clopidogrel varies significantly due to genetic and acquired factors, leading to treatment resistance in some individuals.
- The cytochrome P450 enzyme 2C19 (CYP2C19) is crucial for clopidogrel activation, and genetic variants can impair this process.
Purpose of the Study:
- To review the evidence on pharmacogenetic testing for clopidogrel response.
- To assess the clinical validity and utility of CYP2C19 genetic testing for guiding clopidogrel therapy.
- To summarize available commercial tests for CYP2C19 polymorphisms related to clopidogrel efficacy.
Main Methods:
- Review of scientific literature on CYP2C19 genetics and clopidogrel response.
- Analysis of data regarding clinical validity (accuracy) and clinical utility (patient outcomes) of genetic testing.
- Survey of currently marketed diagnostic tests for CYP2C19 variants.
Main Results:
- Specific CYP2C19 genetic variants are associated with reduced active metabolite levels and diminished platelet inhibition.
- Patients with these variants face an increased risk of major adverse cardiovascular events, including heart attack and stroke.
- Pharmacogenetic testing can identify individuals likely to be poor responders to clopidogrel, enabling alternative treatment strategies.
Conclusions:
- CYP2C19 genotyping is a valuable tool for personalizing anti-platelet therapy.
- Testing can help mitigate risks associated with clopidogrel non-response.
- Consideration of pharmacogenetic testing is warranted for patients undergoing treatment with clopidogrel, particularly those at high cardiovascular risk.
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