A Randomized, Pharmacodynamic Comparison of Low Dose Ticagrelor to Clopidogrel in Patients With Prior Myocardial Infarction

Inclusion criteria

• Provision of informed consent prior to any study specific procedures
• Post-menopausal female (defined as absence of any vaginal bleeding for a year) or male aged >50 years
• A spontaneous MI (ST or Non ST segment elevation) 1 to 3 years before enrolment. In addition, at least one of the following high-risk features: age of 65 years or older, diabetes mellitus requiring medication, a second prior spontaneous MI, multivessel coronary artery disease, or non-end stage renal disease (estimated creatinine clearance of <60 ml per minute).

Exclusion criteria

• Planned use of a P2Y12 receptor antagonist, dipyridamole, cilostazol, or anticoagulant therapy during the study period;
• Known allergy, intolerance, hypersensitivity to ticagrelor or clopidogrel or any excipients,
• Active pathological bleeding, severe hepatic impairment, a bleeding disorder or a history of an ischemic stroke or intracranial bleeding, a central nervous system tumor, or an intracranial vascular abnormality;
• Gastrointestinal bleeding within the previous 6 months or major surgery within the previous 30 days;
• Concomitant use of potent Cytochrome P450 3A4 (CYP3A4) inhibitors (atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin and voriconazole, grapefruit juice over 1 litre daily), CYP3A substrates with narrow therapeutic indices (cyclosporine, quinidine), or inducers (carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampin, and rifapentine).
• Increased risk of bradycardic events (e.g. known sick sinus syndrome or third degree AV block or previous documented syncope suspected to be due to bradycardia unless treated with a pacemaker).
• Inability to adhere to the follow-up requirements or any other reason or condition that the investigator feels would place the patient at increased risk if the investigational therapy is initiated.