COMBAT-MI is an investigator-driven, randomized, double-blind and placebo-controlled clinical trial aimed at evaluating the effect of Remote Ischemic Conditioning and exenatide, alone and in combination, on Myocardial Infarct size in 400 STEMI patients (ST segment elevation myocardial infarction). Patients with TIMI (Thrombolysis in Myocardial Infarction) flow grade > 1 will be excluded. The study has a 2 x 2 factorial design (Remote Ischemic Conditioning , Exenatide, both or neither). The primary end-point will be Myocardial Infarct size measured by Cardiac Magnetic Resonance Imaging (CMRI) performed 3 - 7 days after primary Percutaneous Coronary Intervention (pPCI) (expressed as % of left ventricular (LV) mass). Secondary end-points will include myocardial salvage index, based on angiographic and CMRI derived estimations of the area at risk, and frequency of Major Adverse Cardiovascular Events (MACE) and of major adverse events during admission.