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Drug insight: Clopidogrel nonresponsiveness

Paul A Gurbel1, Udaya S Tantry

  • 1Sinai Center for Thrombosis Research, Baltimore, MD 21215, USA. pgurbel@lifebridgehealth.org

Nature Clinical Practice. Cardiovascular Medicine
|July 1, 2006
PubMed

Insights

Clopidogrel nonresponsiveness contributes to ischemic events despite dual antiplatelet therapy. Understanding variability in drug absorption, metabolism, and interactions is key to overcoming resistance and improving patient outcomes.

Area of Science:

  • Cardiology
  • Pharmacology
  • Thrombosis

Background:

  • Platelet reactivity influences atherothrombosis and ischemic events.
  • Dual antiplatelet therapy with clopidogrel and aspirin is standard for acute coronary syndromes and percutaneous coronary intervention.
  • Despite benefits, stent thrombosis and other ischemic events persist, partly due to clopidogrel nonresponsiveness.

Purpose of the Study:

  • To review clopidogrel response variability and nonresponsiveness.
  • To explore mechanisms underlying nonresponsiveness to clopidogrel.
  • To discuss strategies for overcoming clopidogrel resistance.

Main Methods:

  • Literature review of studies on clopidogrel response and nonresponsiveness.
  • Analysis of factors contributing to variability in drug efficacy.
  • Synthesis of current research on antiplatelet treatment.

Main Results:

  • Nonresponsiveness to clopidogrel is linked to factors like absorption, metabolism, drug interactions, and genetic polymorphisms.
  • These factors impact the conversion of clopidogrel to its active metabolite and its antiplatelet effect.
  • Existing therapeutic strategies may not fully address clopidogrel resistance in all patients.

Conclusions:

  • Clopidogrel nonresponsiveness is a significant clinical issue.
  • Addressing variability in drug response is crucial for preventing ischemic events.
  • Optimizing antiplatelet therapy may involve dose adjustments or alternative P2Y12 inhibitors.

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