Comparison of Antiplatelet Effect of Ticagrelor vs Tirofiban in Patients With Non-ST Elevation Acute Coronary Syndrome

Ticagrelor vs. Tirofiban, Comparison of Anti-platelet Effects in Patients With Non-ST Elevation Acute Coronary Syndrome(TE-CLOT Trial : Ticagrelor's Effect for CLOT Prevention) ; A Single Center, Open-label Randomized Controlled Study

This is a single-center, open-label prospective randomized pharmacodynamic investigation of two anti platelet regimens in patients who are planned to undergo PCI for non-ST segment elevation acute coronary syndrome(NSTE-ACS) for 24 hours

1. Ticagrelor : loading dose(180mg) followed by maintenance dose(90mg bid)

2. Tirofiban : 0.4ug/kg/min for 30min followed by 0.1ug/kg/min

   • both agents will be given on top of aspirin

In combination with aspirin, P2Y12 receptor antagonist or glycoprotein IIb/IIIa inhibitor(GPI) is now a recommended drug as the standard dual antiplatelet regimen in patients with acute coronary syndrome(1).

Ticagrelor is a newly developed oral P2Y12 receptor inhibitor. It shows faster, greater and more consistent platelet inhibition as compared with previous P2Y12 receptor antagonist clopidogrel(2) and it also shows better clinical outcome and similar risk for bleeding as compared with clopidogrel(3).Interestingly, pharmacodynamic data of some studies showed excellent effect of ticagrelor in terms of inhibiting platelet activation apparently as high as that of GPI(2,4).

Primary hypothesis: Ticagrelor have a comparable efficacy in platelet inhibition to GPI in patients with non-ST segment elevation acute coronary syndrome.

Statistical design : non-inferiority test

Inclusion Criteria:

• Patients with recent or current ischemic symptoms at the time of randomization will be eligible if 2 of the following criteria are met: ST-T change indicating ischemia; a positive test of biomarker indication myocardial necrosis; or one of several risk factors(age ≥60 years
• Previous myocardial infarction or coronary artery bypass grafting [CABG]
• Coronary artery disease with stenosis of ≥50% in at least two vessels
• Previous ischemic stroke, transient ischemic attack, carotid stenosis of at least 50%, or cerebral revascularization
• Diabetes mellitus
• Peripheral arterial disease; or chronic renal dysfunction, defined as a creatinine clearance of <60 ml per minute per 1.73 m2 of body surface area)

Exclusion Criteria:

1. Administration of fibrinolytic or any GP IIb/IIIa inhibitors for the treatment of current AMI
2. Major surgery or trauma within 30 days
3. Active bleeding
4. Previous stroke in the last six months
5. Oral anticoagulant therapy
6. Pre-existing thrombocytopenia
7. Vasculitis
8. Hypertensive retinopathy
9. Severe hepatic failure
10. Severe renal failure requiring hemodialysis
11. Documented allergy/intolerance or contraindication to tirofiban or P2Y12 inhibitor
12. Uncontrolled hypertension (systolic or diastolic arterial pressure >180 mmHg or 120, respectively, despite medical therapy)
13. Limited life expectancy, e.g. neoplasms, others
14. Inability to obtain informed consent