Monitoring aspirin and clopidogrel response: testing controversies and recommendations

Area of Science:

• Cardiology
• Pharmacogenomics

Background:

• Dual antiplatelet therapy with clopidogrel and aspirin is standard post-percutaneous coronary intervention for coronary artery disease (CAD).
• High on-treatment platelet reactivity (HPR) is linked to major adverse cardiac events, despite standard therapy.
• Interindividual variability in response to clopidogrel and aspirin contributes to HPR.

Purpose of the Study:

• Review current controversies and evidence regarding antiplatelet therapy effectiveness testing.
• Examine genetic and phenotype-based laboratory tests for aspirin and clopidogrel response.
• Correlate antiplatelet drug response testing with clinical outcomes.

Main Methods:

• Literature review of studies on antiplatelet drug response testing.
• Analysis of genetic and laboratory assays for clopidogrel and aspirin.
• Evaluation of correlations between test results and clinical outcomes (ischemic events, bleeding).

Main Results:

• No gold standard assay for antiplatelet drug response is established.
• Variability in patient response to antiplatelet drugs is a significant factor.
• Testing may identify patients at risk for recurrent ischemic events or bleeding.

Conclusions:

• Antiplatelet therapy effectiveness testing should be considered case-by-case, particularly for acute coronary syndrome or stent thrombosis.
• For stable CAD, targeted testing in specific risk groups may optimize treatment and reduce complications.
• Cost-effectiveness and clinical utility guide decisions on routine testing.