A randomized controlled, open label, multicenter trial with 1000 patients aged 70 years and older, presenting with Non-ST-elevation acute coronary syndrome. Patients will be randomized to either clopidogrel or the novel P2Y12 inhibitor (ticagrelor or prasugrel). Patients will be followed for one year for outcomes such as bleeding episode requiring medical intervention and net clinical benefit (all cause mortality, non-fatal myocardial infarction, non-fatal stroke, PLATO major and minor bleeding).

Inclusion Criteria:

• At least 70 years of age.
• Hospitalization for NSTEMI or UA < 72 hours

Exclusion Criteria:

• Contraindication to P2Y12 inhibitors i.e. clopidogrel, prasugrel or ticagrelor:
• Unable or unwilling to give informed consent or have a life expectancy of less than one year.
• Having received thrombolytic therapy within the previous 24 hours.
• Severe renal function impairment needing dialysis.
• Confirmed or persistent severe hypertension (Systolic Blood Pressure (SBP) > 180 mmHg and/or Diastolic Blood Pressure (DBP) >110 mmHg) at randomization.
• At increased bleeding risk, at the investigator's opinion, e.g. because of malignancy.
• Cardiogenic shock (SBP ≤ 80mmHg for >30 mins) or Intra-Aortic Balloon Pump (IABP) at the time of screening.
• History of major surgery, severe trauma, fracture or organ biopsy within 90 days prior to randomisation.
• Clinically significant out of range values for platelet count or haemoglobin at screening, in the investigator's opinion.
• ACS under dual antiplatelet therapy, e.g. aspirin with a P2Y12 inhibitor; clopidogrel, prasugrel, ticagrelor.
• Patients with a known CYP2C19 genotype at the time of randomization.