Clinical Research Directory

Inclusion Criteria: 1. Age ≥18 years. 2. Significant coronary artery disease (coronary angiogram documentation of Left Main artery lesion ≥50% and/or lesion(s) ≥70% in other coronary arteries, and/or FFR\<0.8 or iFR\<0.9). 3. Completed at least 6 months post ACS (regardless of the bleeding risk, anti-platelet strategy, revascularization strategy "PCI, CABG, or conservative medical management only", before randomization). 4. Agreement to give written informed consent. Exclusion Criteria: 1. History of hypersensitivity to aspirin or clopidogrel. 2. Presence of non-cardiac comorbidity with life expectancy ≤2 years from randomization. 3. Plan for surgery or intervention which requires stopping antiplatelet agents ≥3 months. 4. Females with childbearing potential or breast-feeding. 5. Co-administration of contraindicated medications as follows: anticoagulants (warfarin, direct oral anticoagulants (DOACs), or chronic therapy of heparin); cytochrome P450 2C19 inhibitors (fluoxetine, moclobemid or voriconazole); probenecid; high dose of methotrexate (≥15 mg/week); lithium. 6. Inability to have a complete follow-up for up to 5 years from randomization (e.g: high possibility of travelling outside the country). 7. Inability to afford paying for Clopidogrel out-of-pocket up to 5 years from randomization (in case not being covered by the health care system).