Acetyl Salicylic Elimination Trial JAPAN: The ASET JAPAN Pilot Study

Inclusion Criteria: Inclusion Criteria for CCS patients (phase 1) : 1. Successful PCI with optimal acute stent implantation of one or more SYNERGY stent(s). 2. SYNERGY stent implantation was performed to treat: 1. at least one de novo lesion with ≥50% diameter stenosis determined by visual assessment in at least one native coronary artery with a vessel size between 2.25 mm and 5.0 mm in diameter. 2. Non-acute coronary disease, with normal cardiac biomarker values prior to the PCI procedure, and evidences of myocardial ischemia by symptoms or non-invasive/invasive testing. 3. patients with anatomical SYNTAX Score \< 23 prior to PCI 3. Patient has provided written informed consent as approved by the Ethical Committee of the respective clinical site. Inclusion Criteria for NSTE-ACS patients (phase 2) : 1. Patients with diagnosed Non ST-elevation acute coronary syndrome 2. Patients with anatomical SYNTAX Score \< 23 prior to PCI 3. Patient provided written informed consent as approved by the Ethical Committee of the respective clinical site Post PCI criteria for NSTE-ACS patients 1. Patient is free of angina symptoms at the end of PCI procedure. 2. Successful PCI with optimal acute stent implantation of one or more SYNERGY stent(s). 3. SYNERGY stent implantation was performed to treat at least one de novo lesion with ≥50% diameter stenosis determined by visual assessment in at least one native coronary artery with a vessel size between 2.25 mm and 5.0 mm in diameter. Exclusion Criteria: Exclusion Criteria for CCS patients (phase 1): Candidates will be ineligible for enrolment in the study if any of the following conditions apply: 1. ≤ 20 years of age 2. Unable to give Informed Consent 3. Females of child-bearing potential unless negative pregnancy test at screening and willing to use effective contraception for the duration of treatment with study medication 4. Female who is breastfeeding at time of enrolment 5. Patients concomitantly received any other non-study stent at the same procedure 6. Patients with planned PCI or surgical intervention to treat any cardiac or non-cardiac condition; 7. Previous PCI with any non-SYNERGY stents in the last 6 months 8. Current (same hospitalization) or previous (within 12 months) acute coronary syndrome 9. Patient with following lesion characteristics prior to PCI; Saphenous or arterial graft, in-stent (re)stenosis 10. History of definite stent thrombosis 11. Concomitant cardiac valve disease requiring invasive therapy 12. Atrial fibrillation or other indication for oral anticoagulant therapy 13. Known allergy to aspirin, prasugrel or diagnosed lactose intolerance 14. Acute heart failure 15. Active myocarditis 16. Cardiomyopathy 17. Patient in hemodialysis 18. Treatment in the last 10 days or requirement for ongoing treatment with a strong CYP3A4 inhibitor or inducer; 19. History of stroke or transient ischemic cerebrovascular accident 20. History of intracranial hemorrhage or other intracranial pathology associated with increased bleeding risk 21. Hemoglobin \<10 g/dL or other evidence of active bleeding 22. Peptic ulceration documented by endoscopy within the last 3 months unless healing proven by repeat endoscopy 23. Any other condition deemed by the investigator to place the patient at excessive risk of bleeding with prasugrel 24. Participation in another trial with an investigational drug or device 25. Co-morbidity associated with life expectancy \<1 year 26. Assessment that the subject is not likely to comply with the study procedures or have complete follow-up 27. Known drug or alcohol dependence within the past 12 months as judged by the investigator Exclusion Criteria for NSTE-ACS patients (Phase 2): Candidates will be ineligible for enrolment if any of the following conditions apply: 1. ≤ 20 years of age 2. Unable to give Informed Consent 3. Females of child-bearing potential unless negative pregnancy test at screening and willing to use effective contraception for the duration of treatment with study medication 4. Female who is breastfeeding at time of enrolment 5. Patients concomitantly received any other non-study stent at the same procedure 6. Patients with planned PCI or surgical intervention to treat any cardiac or non-cardiac condition; 7. Previous PCI with any non-SYNERGY stents in the last 6 months 8. Patient with following lesion characteristics prior to PCI; Saphenous or arterial graft, in-stent (re)stenosis 9. History of definite stent thrombosis 10. Concomitant cardiac valve disease requiring invasive therapy 11. Known allergy to aspirin, prasugrel or diagnosed lactose intolerance 12. Atrial fibrillation or other indication for oral anticoagulant therapy; 13. History of stroke or transient ischemic cerebrovascular accident 14. History of intracranial haemorrhage or other intracranial pathology associated with increased bleeding risk 15. Acute heart failure 16. Active myocarditis 17. Cardiomyopathy 18. Patient in hemodialysis 19. Haemoglobin \<10 g/dL or other evidence of active bleeding 20. Hemodynamic instability or cardiogenic shock 21. Recurrent or ongoing chest pain refractory to medical treatment 22. Life-threatening arrhythmias or cardiac arrest; 23. Mechanical complications of myocardial infarction 24. Recurrent dynamic ST-T wave changes, particularly with intermittent ST-elevation 25. Peptic ulceration documented by endoscopy within the last 3 months unless healing proven by repeat endoscopy 26. Any other condition deemed by the investigator to place the patient at excessive risk of bleeding with prasugrel 27. Participation in another trial with an investigational drug or device 28. Co-morbidity associated with life expectancy \< 1 year 29. Assessment that the subject is not likely to comply with the study procedures or have complete follow-up; 30. Known drug or alcohol dependence within the past 12 months as judged by the investigator