Genetic considerations

Area of Science:

• Pharmacogenomics
• Cardiovascular Medicine
• Clinical Pharmacology

Background:

• Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is standard for acute coronary syndrome (ACS) and percutaneous coronary intervention (PCI).
• CYP2C19 genetic polymorphisms leading to loss of function are associated with reduced clopidogrel efficacy and increased cardiovascular events, especially stent thrombosis.
• The impact of CYP2C19 genotype on newer P2Y12 inhibitors like prasugrel and ticagrelor appears minimal, though they carry increased bleeding risks.

Purpose of the Study:

• To review the impact of genetic polymorphisms, particularly CYP2C19, on antiplatelet therapy response in ACS patients.
• To evaluate the clinical implications of these genetic variations on cardiovascular event risk and bleeding.
• To explore the potential of a pharmacogenomic-guided approach to optimize antiplatelet therapy.

Main Methods:

• Review of candidate gene and genome-wide association studies.
• Analysis of meta-analyses from registries and genetic substudies of randomized clinical trials.
• Comparison of clopidogrel response with CYP2C19 genotype versus newer P2Y12 inhibitors.

Main Results:

• CYP2C19 loss-of-function polymorphisms reduce clopidogrel's active metabolite exposure and antiplatelet effect.
• Carriers of these polymorphisms treated with clopidogrel show higher risks of cardiovascular events and stent thrombosis, particularly in PCI patients.
• The effect of CYP2C19 genotype on prasugrel and ticagrelor efficacy seems negligible, but these drugs increase bleeding risk.

Conclusions:

• CYP2C19 genotype influences clopidogrel's effectiveness and safety in ACS patients.
• A pharmacogenomic-guided strategy for antiplatelet therapy in ACS may balance ischemic benefits and bleeding risks.
• Further randomized clinical trial data are needed to confirm the utility of genotype-guided antiplatelet selection.