Reloading Prasugrel or Clopidogrel on High Platelet Reactivity Before Percutaneous Coronary Intervention
Condition: Acute Coronary Syndrome
MeSH terms: Acute Coronary Syndrome
Study type: Interventional
Phase: Phase 3

Summary: 
      High platelet reactivity unit (PRU) after loading dose clopidogrel in patients undergoing
      percutaneous coronary intervention (PCI) is related to high risk of short and long term
      recurrent ischemic events including stent thrombosis.

      The investigators hypothesize that additional loading of prasugrel in patients with high PRU
      after clopidogrel loading would be superior to additional loading of clopidogrel in reducing
      platelet reactivity and thereby result in lower risk of short term recurrent ischemic events.
    

Detailed description: 
      Dual antiplatelet therapy with acetylsalicyclic acid (ASA) and additional clopidogrel is now
      standard regimen for the prevention of recurrent ischemic events in patients who undergo PCI.

      But decreased effect of clopidogrel in a group of patients was reported and they are known to
      be associated with high risk of recurrent ischemic event. Decreased effect of clopidogrel is
      mainly resulted from decreased function to metabolite prodrug, clopidogrel to active form of
      drug.

      Prasugrel, newer thienopyridine has been recently developed and showed advantages to
      clopidogrel. Prasugrel is known to have shorter onset time to achieve steady state level than
      clopidogrel and constant pharmacologic effect regardless of patient diversity.

      High PRU after loading dose clopidogrel in patients undergoing PCI is known to be related to
      increased risk of short and long term recurrent ischemic events including stent thrombosis.
      Prasugrel has been reported to be effective in reducing platelet reactivity in patients
      showing resistance to clopidogrel and high PRU.

      The investigators hypothesize that additional loading of prasugrel in patients with high PRU
      after clopidogrel loading would be superior to additional loading of clopidogrel in reducing
      platelet reactivity and thereby result in reduced risk of short term recurrent ischemic
      events.

      The investigators plan to include 70 acute coronary syndrome patients who are planned to
      undergo PCI and show high platelet reactivity. Most patients with ACS administer loading dose
      of ASA and clopidogrel as soon as they are assumed to be ACS.

      The investigators plan to perform platelet reactivity test by VeryfyNow (VN) before PCI and
      enroll patients with high PRU defined by 235 or more. They are to randomly administered
      additional 300mg of clopidogrel or 20mg of prasugrel.
    

Intervention name(s): Prasugrel; Clopidogrel
Intervention type(s): Drug; Drug
Intervention description(s): Reloading with prasugrel 20mg and followed by daily administration of prasugrel 5mg for 30 days; Reloading with clopidogrel 300mg and followed by daily administration of clopidogrel 75mg for 30 days
Other intervention name(s): Effient; Plavix
Intervention MeSH terms: Clopidogrel; Prasugrel Hydrochloride
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: High plate reactivity unit after loading dose of clopidogrel