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Variability of response to clopidogrel: possible mechanisms and clinical implications

Theresa Nguyen1, William H Frishman, James Nawarskas

  • 1Department of Medicine, Virginia Mason Medical Center, Seattle, Washington, USA.

Cardiology in Review
|April 22, 2006
PubMed

Insights

Clopidogrel effectively reduces thrombotic events but response varies significantly. Factors like dosing, drug interactions, and genetics impact its antiplatelet effects, necessitating better screening methods.

Area of Science:

  • Pharmacology
  • Cardiovascular Medicine
  • Clinical Trials

Background:

  • Clopidogrel is a key antiplatelet medication used to prevent arterial thrombotic events.
  • Clinical studies confirm its efficacy in reducing thrombotic risk.
  • However, a significant portion of patients (up to 30%) exhibit variable responses to clopidogrel's antiplatelet effects.

Purpose of the Study:

  • To investigate the reasons behind variable patient responses to clopidogrel.
  • To identify factors contributing to the attenuated clinical benefit of clopidogrel.
  • To explore the need for improved laboratory methods for assessing clopidogrel response variability.

Main Methods:

  • Review of clinical studies on clopidogrel efficacy and response variability.
  • Analysis of potential contributing factors including dosing, drug interactions, and genetic polymorphisms.
  • Discussion on the current limitations in laboratory procedures for screening clopidogrel response.

Main Results:

  • Clopidogrel effectively inhibits adenosine diphosphate-induced platelet aggregation.
  • Variability in patient response can attenuate the drug's clinical benefit.
  • Identified contributing factors include incorrect dosing, drug-drug interactions, and genetic variations.

Conclusions:

  • Patient response variability to clopidogrel is a significant clinical challenge.
  • Multiple factors contribute to this variability, impacting treatment effectiveness.
  • Further research is needed to establish optimal laboratory procedures for screening clopidogrel response variability.

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