Primary Objective: To test if 600 mg of clopidogrel loading dose administered ≥ 6 and ≤ 24 hours prior to PCI produce a greater decrease of periprocedural release of biochemical markers (CK, CK-MB, and troponin-T and/or I) of myocardial necrosis, compared to 300 mg loading dose, given ≥ 6 and ≤ 24 hours prior to PCI or 600 mg loading dose of clopidogrel, administered immediately (≤ 45 minutes) before PCI.

Inclusion Criteria:

• Patients having symptomatic coronary artery disease with objective evidence of ischemia (eg, symptoms of angina pectoris, positive stress test results or dynamic electrocardiographic (ECG) changes).
• Patients undergoing stent implantation

Exclusion Criteria:

• Any known contraindication to the use of aspirin or clopidogrel.
• Patients receiving clopidogrel within 10 days, thrombolytics within 24 hours or receiving oral anticoagulation therapy
• Elective administration of IIb/IIIa inhibitors.
• Cardiogenic shock
• Acute MI< 24 hours
• BP systolic <100 mmHg
• Left ventricular ejection fraction < 30%
• Heart failure, NYHA class III or IV
• Severe renal insufficiency (creatinine > 3.0 mg/dL)
• Platelet count <100,000/mm³
• Target lesion in a venous bypass graft
• Target lesion in a chronic occlusion

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.