Main Inclusion Criteria:  Discharged with a confirmed diagnosis of symptomatic type 1 acute myocardial infarction (AMI) ST-Elevation Myocardial Infarction (STEMI) or Non-ST-Elevation Myocardial Infarction (NSTEMI), no longer than 4 weeks prior to randomization.  Presence of either a second prior AMI within 1 year of screening or at least 2 of the following risk factors:  Second prior AMI more than 1 year before screening. Diabetes mellitus defined by ongoing glucose lowering treatment. Chronic kidney disease with estimated glomerular filtration rate less-than 60 mL/min/1.73 m2. Multivessel coronary artery disease. Peripheral artery disease. Age greater than or equal to 65 years. Absence of coronary revascularization of the qualifying AMI. Active daily smoking at screening. Successful self-administered placebo according to the autoinjector instruction for use training during screening.  Main Exclusion Criteria:  Increased risk of serious bleeding including any of the following:  History of intracranial bleed at any time. Known uncorrected intracranial vascular abnormality. Gastrointestinal bleed requiring hospitalization or transfusion within 1 year prior to screening. Already on oral triple antithrombotic therapy (i.e., Dual antiplatelet therapy and oral anticoagulant). Known liver impairment significantly affecting the hepatic function. Current dialysis. Ischemic stroke or transient ischemic attack within 3 months of screening. Chronic anemia with hemoglobin < 10 g/dL. Chronic thrombocytopenia with platelet count < 100,000/mm3. Known hypersensitivity to selatogrel, any of its excipients, or drugs of the P2Y12 class. Previous exposure to an investigational drug within 3 months prior to randomization. Participation in another clinical trial with an investigational product or device within 3 months prior to randomization.