Personalizing antiplatelet prescribing using genetics for patients undergoing percutaneous coronary intervention.

INTRODUCTION: Clopidogrel is commonly prescribed with aspirin to reduce the risk for adverse cardiovascular events after percutaneous coronary intervention (PCI). However, there is significant inter-patient variability in clopidogrel response. The CYP2C19 enzyme is involved in the biotransformation of clopidogrel to its pharmacologically active form, and variation in the CYP2C19 gene contributes to clopidogrel response variability. Areas covered. This article describes the impact of CYP2C19 genotype on clopidogrel pharmacokinetics, pharmacodynamics, and effectiveness. Examples of clinical implementation of CYP2C19 genotype-guided antiplatelet therapy for patients undergoing PCI are also described as are emerging outcomes data with this treatment approach. Expert commentary. A large clinical trial evaluating outcomes with CYP2C19 genotype-guided antiplatelet therapy after PCI is on-going. In the meantime, data from pragmatic and observational studies and smaller trials support improved outcomes with genotyping after PCI and use of alternative antiplatelet therapy in patients with a CYP2C19 genotype associated with reduced clopidogrel effectiveness.