Phase IV Study to Compare Efficacy and Safety of Plavix 75mg With Astrix 100mg and Closone

Inclusion Criteria: * Subjects under a stable condition after Post-Percutaneous Coronary Artery Intervention over three months * 20\~86 years old * Willing to adhere to protocol requirements and sign a informed consent form Exclusion Criteria: * Subject who did not undergo or failed Drug-Stent Implantation * Subjects who took an anti-coagulant, anti-thrombotic regularlly( ≥ 2weeks in a month) before the study, or plan to have continuous treatment during the study(Except Aspirin alone or combination of Aspirin and Clopidogrel) * Subjects with a history of substance or alchol abuse * Subjects with a history of hypersensitivity to Clopidogrel, Aspirin or other NSAIDS * Subjects having Aspirin or other NSAIDs-induced Asthma or history * Subjects with Severe hepatopathy(AST and ALT \> 5 times the upper limit of normal) * Subjects with Severe nephropathy(Cr \> 3 times the upper limit of normal) * Subjects with hemorrhage like gastric ulcer, intracranial hemorrhage etc. * Subjects with high risk of hemorrhage like blood coagulation disorders, uncontrolled severe hypertension, active bleeding, history of severe bleeding * subjects who are pregnant, breastfeeding * Subjects not using medically acceptable birth control * Subjects who are unsuitable to take the Investigational product due to a medical/mental condition * Subjects inherently having Galactose malobsorption, Lactase deficiency or Glucose-Galactose malobsorption