CYP2C19 Pharmacogenomic Testing
Why Genotyping Changes Outcomes
Understanding the genetic factors in Clopidogrel activation.
Pro-drug Activation
Clopidogrel requires activation by the CYP2C19 enzyme. Loss-of-function alleles can reduce active metabolite exposure 5 to 10-fold.
Clinical Risk
Intermediate & Poor Metabolizers (IM/PM) have significantly higher rates of stent thrombosis and major adverse cardiovascular events (MACE).
Recent Meta-analysis
Genotype-guided therapy lowered MACE by 30% in IM/PM patients compared to standard clopidogrel treatment.
| Group | How common are slow genes? | What that means for clopidogrel |
|---|---|---|
| East & South-East Asians | ≈ 1/2 people | Standard dose often too weak |
| Europeans | ≈ 1/4 people | Many do well, some need adjustment |
| Africans / African-Americans | ≈ 1/5 people | Mixed response; test to be sure |
| Hispanic / Latino | ≈ 1/ 5 people | Similar to African ancestry |
Who Should Be Tested?
Identifying ideal candidates for pharmacogenomic testing.
ACS or PCI Patients
Highest evidence and benefit for genotype-guided therapy.
History of Stent Thrombosis
May indicate a possible loss-of-function (LOF) allele carrier.
Stroke / TIA Patients
Genotype affects the risk of recurrence on clopidogrel monotherapy.
East-Asian Ancestry
Nearly half of this population are IM or PM, where LOF alleles are common.
High Bleeding Risk
Genotype info helps balance efficacy vs. bleeding risk with potent alternatives.
Your Journey with Genolife Services
A streamlined process for personalized antiplatelet therapy.
Pre-test Counselling
Discuss benefits, limits, inheritance, and alternative antiplatelet options.
Sample Collection
Conveniently provide a 3 mL EDTA blood sample or use a saliva kit.
Expert Interpretation
Reviewed by a team including a Clinical Geneticist, Pharmacologist & Interventional Cardiologist.
Post test
Offered for relatives with CAD who may also need antiplatelet therapy.
Ready to plan for a safer health future?
Contact us for a consultation with our Genetic Counselor/Pharmacogenomics Specialist about the Clopidogrel Response Panel or other genetic tests.
References
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- Hershfield MS et al. CPIC Guideline for HLA-B Genotype and Allopurinol Dosing. Clin Pharmacol Ther. 2013.
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- Saito Y et al. CPIC guideline update review, 2015.
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- NCBI GeneReviews®. Allopurinol Therapy and HLA-B*58:01 Genotype. 2020 update.
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- ACR Gout Management Guideline. 2020.
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- Somkrua R et al. Meta-analysis: OR ≈ 74 for SJS/TEN in HLA-B*58:01 carriers. Pharmacoepidemiol Drug Saf. 2011.
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- Puangpetch A et al. HLA-B allele diversity in Thais: 16 % HLA-B*58:01. Hum Immunol. 2015.
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- Tassaneeyakul W et al. Allopurinol-induced SJS/TEN and HLA-B*58:01 in Thai patients: sensitivity 100 %, specificity 87 %. Clin Pharmacol Ther. 2009.
