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A Method to Study the C924T Polymorphism of the Thromboxane A2 Receptor Gene
Published on: April 1, 2019
Tailored Thienopyridine therapy: no urgency for CYP2C19 genotyping.
Pierre Fontana1, Marco Cattaneo, Christophe Combescure
1Division of Angiology and Haemostasis, Geneva University Hospital and Faculty of Medicine.
Journal of the American Heart Association
|March 30, 2013
Summary
The CYP2C19*2 gene variant has limited value in predicting high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel, an anti-platelet drug. Routine CYP2C19 genotyping is not recommended for tailoring anti-P2Y12 therapy.
Area of Science:
- Pharmacogenomics
- Cardiovascular Medicine
- Clinical Pharmacology
Background:
- Clopidogrel, an anti-P2Y12 drug, is widely used for cardiovascular patients.
- A significant percentage of patients exhibit high on-treatment platelet reactivity (HTPR), increasing risks of major adverse cardiovascular events (MACE).
- The CYP2C19*2 genetic variant is being considered for tailoring anti-P2Y12 therapy.
Purpose of the Study:
- To evaluate the clinical utility of the CYP2C19*2 genotype for predicting HTPR in patients treated with clopidogrel.
- To assess the effectiveness of CYP2C19*2 genotyping in guiding anti-P2Y12 treatment strategies.
Main Methods:
- Systematic review and meta-analysis of seven studies comparing CYP2C19*2 genotyping with VASP assay for HTPR prediction.
- Analysis of summarized sensitivity and negative likelihood ratio of CYP2C19*2 for HTPR.
Main Results:
- The CYP2C19*2 genotype showed a summarized sensitivity of 37.6% for predicting HTPR.
- The negative likelihood ratio was 0.77, indicating limited predictive value.
- Tailoring therapy based solely on CYP2C19*2 status may miss non-carrier patients with HTPR.
Conclusions:
- CYP2C19*2 genotyping has limited value as a routine clinical aid for predicting HTPR and guiding anti-P2Y12 therapy.
- Current evidence does not support the routine use of CYP2C19*2 genotyping for tailoring clopidogrel treatment.
- Integrated strategies involving genotyping, phenotyping, and clinical data may offer a more promising approach.
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