Assessment of clopidogrel non-response by the PFA-100 system using the new test cartridge INNOVANCE PFA P2Y

Ann Hematol. 2010 Jun;89(6):597-605. doi: 10.1007/s00277-009-0881-9. Epub 2010 Jan 5.


Until now, the PFA-100 system has been considered unsuitable for monitoring clopidogrel efficacy. The authors evaluated platelet function in peripheral arterial occlusive disease (PAOD) patients using a new PFA-100(R) test cartridge (product name: INNOVANCE PFA P2Y*) specifically designed for this purpose. Twenty-two stable PAOD patients on antithrombotic therapy with clopidogrel alone (n = 22) and 18 patients undergoing a peripheral catheter intervention, preliminarily treated with 100 mg/day of aspirin followed by co-administration of clopidogrel (loading dose 300 mg, maintenance dose 75 mg/day), were enrolled in this study. Defining non-responsiveness to clopidogrel as an aggregation response within the reference range (90% central interval), four (18.2%) non-responders using light transmittance aggregometry (LTA) induced by 5 microM adenosine diphosphate (ADP) and six (27.3%) non-responders using LTA induced by 2 microM ADP (LateAggr >72.1% and >42.9%, respectively) were identified. INNOVANCE PFA P2Y* determined six (27.3%) non-responders (CT < 87 s). Agreement between the two aggregometry assays and INNOVANCE PFA P2Y* on the definition of clopidogrel response and non-response exceeded 70%. Only three patients were uniformly identified as clopidogrel non-responders by all three assays. When clopidogrel was co-administered with aspirin, two (11.1%) non-responders to clopidogrel were detected with INNOVANCE PFA P2Y*, whereas ADP-induced LTA found all patients to be responsive. INNOVANCE PFA P2Y* appears to be suitable for monitoring the effect of clopidogrel on platelet function. Its sensitivity in detecting responsiveness or non-responsiveness to clopidogrel is comparable to ADP-induced LTA. Additional prospective studies are needed to clarify the clinical relevance of the test results and classification obtained with INNOVANCE PFA P2Y*.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Arterial Occlusive Diseases / blood
  • Arterial Occlusive Diseases / diagnosis*
  • Arterial Occlusive Diseases / drug therapy*
  • Aspirin / administration & dosage
  • Blood Platelets / pathology
  • Blood Platelets / physiology
  • Catheterization, Peripheral / methods
  • Clopidogrel
  • Diagnostic Techniques, Cardiovascular / instrumentation*
  • Female
  • Fibrinolytic Agents / administration & dosage
  • Hemostasis / drug effects
  • Humans
  • Male
  • Middle Aged
  • Peripheral Vascular Diseases / blood
  • Peripheral Vascular Diseases / diagnosis*
  • Peripheral Vascular Diseases / drug therapy*
  • Platelet Aggregation Inhibitors / administration & dosage
  • Prognosis
  • Reagent Kits, Diagnostic*
  • Ticlopidine / administration & dosage
  • Ticlopidine / analogs & derivatives*
  • Treatment Failure


  • Fibrinolytic Agents
  • Platelet Aggregation Inhibitors
  • Reagent Kits, Diagnostic
  • Clopidogrel
  • Ticlopidine
  • Aspirin