Long Term Follow-up of Comparison of Clopidogrel vs. Aspirin Monotherapy After Drug-eluting Stent Implantation

Study Overview
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Brief Summary
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This is an retrospective extended study of a randomized clinical trial (The HOST-EXAM trial ClinicalTrials.gov Identifier: NCT02044250). Investigators will perform a retrospective analysis of all participants enrolled in this trial will be performed, until the longest follow-up duration.

Detailed Description
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The HOST-EXAM trial (ClinicalTrials.gov Identifier: NCT02044250) was an randomized clinical trial that was performed to compare head-to-head, the efficacy and safety between aspirin and clopidogrel monotherapy in patients who received PCI for coronary artery disease and required chronic maintenance antiplatelet therapy. From March 2014 through May 2018, a total of 5438 patients were enrolled, and follow-up was performed upto 24 months after randomization. After this study, randomization was unlocked and patients were followed-up based on the standard protocol. Afterwards, the current study was planned to perform a extended follow-up of the HOST-EXAM population. The specific drug by the randomization group in the HOST-EXAM trial was not mandatory after the initial 24 months, therefore participants received medication according to the current guidelines, and according to the physicians preferences. This is a observational, retrospective analysis of all clinical events after the randomization period. The prescribed medications and any clinical events will be evaluated.

Official Title
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HOST-EXAM-Ex : Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis - EXtended Antiplatelet Monotherapy - EXtended Follow up

Conditions
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Coronary Artery Disease, Atheroscleroses, Coronary

Intervention / Treatment
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* Drug: Antiplatelet Agents


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who were enrolled in the HOST-EXAM randomized clinical trial Exclusion Criteria: None, otherwise the patient refuses to participate in this study, or refuses to provide personal medical information

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Clopidogrel group<br>This group are those who received clopidogrel 75mg qd as a single antiplatelet agent therapy after PCI. | Drug: Antiplatelet Agents<br>* Patients who received a single antiplatelet agent will be analyzed according to the prescribed antiplatelet agent<br>|
| Aspirin group<br>This group are those who received aspirin 100mg qd as a single antiplatelet agent therapy after PCI. | Drug: Antiplatelet Agents<br>* Patients who received a single antiplatelet agent will be analyzed according to the prescribed antiplatelet agent<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient oriented composite outcome | A composite of all-cause death, nonfatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and major bleeding complication | From date of randomization until March, 2022. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thrombotic outcome | cardiac death, non-fatal MI, ischemic stroke, readmission due to ACS, and definite or probable stent thrombosis | From date of randomization until March, 2022. | 
| Bleeding outcome | Bleeding Academic Research Consortium (BARC) type ≥2 bleeding | From date of randomization until March, 2022. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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percutenous coronary intervention, drug-eluting stent, chronic maintenance period