Aspirin Impact on Platelet Reactivity in Acute Coronary Syndrome Patients on Novel P2Y12 Inhibitors Therapy
Condition: Acute Coronary Syndrome; Platelet Function and Reactivity Tests; Novel P2Y12 Inhibitors
MeSH terms: Acute Coronary Syndrome; Syndrome
Study type: Interventional
Phase: Phase 4

Summary: 
      Thus far, no study has evaluated the impact on aspirin in addition to the newer and more
      potent P2Y12 inhibitors, among ACS patients and current guidelines recommend dual
      anti-platelet therapy consisting of aspirin and a novel P2Y12 inhibitor in this population.

      Objective The investigators goal is to examine the effect of aspirin in addition to new
      anti-platelet agent (ticagrelor\prasugrel) on platelet reactivity in comparison with placebo,
      among ACS patients treated percutaneously.

      Design The proposed study is a randomized-controlled, double blind trial, conducted among ACS
      patients treated percutaneously. Eligible patients will recruited during hospitalization due
      to ACS after percutaneous coronary intervention (PCI), and randomization by envelopes on 1:1
      basis will take place a month after the index event, at a follow-up visit at the cardiac
      clinic.

      Platelet function and Endothelial function tests will be taken a month after the index event,
      and at a 2 weeks periods following aspirin/placebo therapy, cross-over and return to
      open-label aspirin.

      End-points platelet function tests will be compared between aspirin and placebo therapy and
      before and after the cross-over.
    

Detailed description: 
      Introduction:

      Current knowledge and data support the use of dual anti-platelets for patients after acute
      coronary syndrome (ACS). Novel P2Y12 inhibitors have shown their superiority on clopidogrel
      in regarding morbidity and mortality, but at the cost of higher bleeding rates - even in
      lower doses of aspirin there is increase risk for gastrointestinal (GI) bleeding. In a
      geographical analysis of the PLATO trial it has been shown difference at outcome. When higher
      dose of aspirin were used, the superiority of ticagrelor was reduced.

      The use of platelet reactivity tests have been proved and acknowledged in their usefulness
      for gauging bleeding and ischemic risks. Few studies have shown that clopidogral is
      inhibiting not only the ADP activity, but also the arachidonic acid (AA) pathway that is
      considered aspirin specific pathway. Examining the effect of potent P2Y12 inhibitors in
      healthy volunteers have shown increased inhibition of the AA pathway. Not only that the
      adding of aspirin, have shown little effect on inhibition of AA pathway.

      It has been demonstrated that vascular endothelial function is inversely correlated to
      platelet reactivity in both individuals without established cardiovascular disease (controls)
      and acute myocardial infarction patients.

      Objective Our goal is to examine the effect (platelet function test and endothelial function)
      of aspirin while added to novel P2Y12 inhibitors treated ACS patients.

      Design The proposed study is a randomized-controlled, double blind trial, conducted among ACS
      patients treated percutaneously. Eligible patients will recruited during hospitalization due
      to ACS after percutaneous coronary intervention (PCI), and randomization by envelopes on 1:1
      basis will take place a month after the index event, at a follow-up visit at the cardiac
      clinic.

      Platelet function and Endothelial function tests will be taken a month after the index event,
      and at a 2 weeks periods following aspirin/placebo therapy, cross-over and return to
      open-label aspirin.

      Study end-points The primary end-point is platelet function tests in response to AA.
      Secondary end-points will include endothelial function and platelet reactivity according to
      the platelet activity and VerifyNow test in response to ADP and platelet activation Clinical
      outcomes including all-cause and cardiac mortality and hospitalizations, recurrent ischemia
      and stent thrombosis, and bleeding events along with blood transfusions, will be recorded as
      safety end-points.
    

Intervention name(s): Aspirin
Intervention type(s): Drug
Intervention description(s): Aspirin 100 mg vs. placebo in ACS patients on P2Y12 inhibitors a month following PCI.
Intervention MeSH terms: Aspirin
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: novel P2Y12 inhibitors; aspirin; platelet reactivity; acute coronary syndrome