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Implementation of In Vitro Drug Resistance Assays: Maximizing the Potential for Uncovering Clinically Relevant Resistance Mechanisms
08:46

Implementation of In Vitro Drug Resistance Assays: Maximizing the Potential for Uncovering Clinically Relevant Resistance Mechanisms

Published on: December 9, 2015

Aspirin and clopidogrel resistance

Erin D Michos1, Reza Ardehali, Roger S Blumenthal

  • 1Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.

Mayo Clinic Proceedings
|April 14, 2006
PubMed

Insights

Many patients experience recurrent cardiovascular events despite aspirin and clopidogrel therapy due to resistance. This review explores resistance phenomena, diagnostic challenges, contributing factors, and novel therapies for improved antiplatelet treatment.

Area of Science:

  • Cardiology
  • Pharmacology
  • Thrombosis

Background:

  • Aspirin and clopidogrel are crucial for preventing cardiovascular events.
  • Recurrent cardiovascular events occur in a subset of patients on antiplatelet therapy.
  • Resistance or hypo-responsiveness to these drugs contributes to treatment failure.

Purpose of the Study:

  • To review clinical aspirin and clopidogrel resistance (treatment failure).
  • To discuss the complexities in defining and identifying drug resistance.
  • To identify factors contributing to resistance and explore new therapeutic options.

Main Methods:

  • Literature review of clinical studies and platelet function assays.
  • Analysis of factors influencing antiplatelet drug efficacy.
  • Examination of current guidelines and emerging therapies.

Main Results:

  • Clinical resistance to aspirin and clopidogrel is a recognized phenomenon.
  • Defining and measuring resistance is complex, with no universally accepted assay.
  • Various factors, including genetic and clinical, may influence patient response.

Conclusions:

  • Resistance to aspirin and clopidogrel poses a significant clinical challenge.
  • Further research is needed to standardize resistance testing.
  • New antiplatelet agents may offer alternatives for resistant patients.

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