Intervention: Clopidogrel
Trial phase: Phase 4
ATC code: B01AC04
SMILES: [H][C@@](C(=O)OC)(c1ccccc1Cl)N1CCc2sccc2C1
Sex: All
Age groups: Adult | Older Adult
Healthy volunteers: No
Participants at risk: 5
Group description: Participants randomized to the G-D group will have CYP2C19 genotype analysis performed. CYP2C19 extensive and ultrarapid metabolizers will receive clopidogrel.

clopidogrel: clopidogrel 75 mg/day plus aspirin 81-162 mg/day for one year
Eligibility criteria:
Inclusion Criteria:

Males or non-pregnant females between the ages of 20 and 74 years, inclusive
Not more than four days post-PCI (percutaneous coronary intervention) with placement of one or more drug eluting or bare metal stents
One or more stent(s) delivered with final TIMI 3 flow (thrombolysis in myocardial infarction grade 3) in the stented vessel(s)

Must have evidence of one of the following:

Three vessel disease;
Two vessel disease with one of the following: estimated creatinine clearance <60, prior myocardial infarction, diabetes mellitus on treatment, peripheral artery disease, cerebrovascular disease, bifurcation stent, overlapping stents, or total stent deployment length > 40 mm in length;
Single vessel disease with two of the following: estimated creatinine clearance <60, prior myocardial infarction, diabetes mellitus on treatment, peripheral artery disease, cerebrovascular disease, bifurcating stenting, overlapping stents, or total stent deployment length > 40 mm in length.
Patients with acute MI (myocardial infarction) preceding the PCI must have CK-MB (bound combination of creatine kinase M and creatine kinase B) value lower than the prior value, before randomization
Patients with peri-procedural MI, defined by CK-MB three times greater than upper reference limit (URL), must have CK-MB value lower than the prior value, before randomization. Peri-procedural MI will be screened per clinical suspicion.
Have an indication for one year of dual anti-platelet therapy with a P2Y12 inhibitor and aspirin
Agreement of the treating physician to prescribe anti-platelet therapy according to randomization and study dosing algorithm
Ability to understand and comply with planned study procedures
Provide written informed consent prior to study entry
Agrees to authorize the collection and release of his/her medical information for the duration of the trial or until the subject withdraws

Exclusion Criteria:

History of a gastrointestinal bleed within three months or a major, life threatening bleeding event (e.g., sub-arachnoid or intracranial hemorrhage)
Active pathological bleeding (e.g. GI bleeding)
History of bleeding diathesis or coagulopathy
History of stroke or transient ischemic attack (TIA)
Non-cardiac surgery within the prior 3 months
Planned cardiac or non-cardiac surgery within the next 12 months
CYP2C19 genotype already known to subject or research team from prior genetic testing
Post-PCI CABG (coronary artery bypass graft) before randomization
Planned warfarin or dabigatran therapy any time during the study period
Known allergy to aspirin, clopidogrel or prasugrel
Platelet count <100,000/mm3
Hematocrit < 25%
Pregnancy
Concurrent enrollment in another trial that involves an investigational stent, antithrombotic or anti-platelet agent
Any condition that would, in the opinion of the site investigator, place them at an unacceptable risk or render them unable to meet the requirements of the protocol
Any subject, in the opinion of the investigator, not expected to tolerate or be adherent with one year of dual antiplatelet therapy