Background: The safety and efficacy of ticagrelor in patients with ST-elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remain uncertain. Objectives: The primary objective of the TicagRElor in pAtients with ST elevation myocardial infarction treated with Thrombolysis (TREAT) trial is to evaluate the short-term safety of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy. Key secondary objectives are to assess the safety and efficacy of ticagrelor compared with clopidogrel at 12-months. Design: The TREAT trial is a multicenter, randomized, phase III, Prospective randomized open blinded end-point (PROBE) study that enrolled 3,799 patients in 152 sites from 10 countries. Following administration of fibrinolytic therapy patients were randomized to a loading dose of ticagrelor 180 mg or clopidogrel 300 mg followed by a maintenance dose of ticagrelor 90 mg twice daily or clopidogrel 75 mg/day for 12-months. The primary outcome is the rate of TIMI major bleeding at 30-days and will be assessed for non-inferiority using an intention-to-treat analysis. Co-treatments include aspirin and anticoagulants. Other evidence based therapies are also recommended. Secondary efficacy outcome include a composite of death from vascular causes, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack or other arterial thrombotic event. All-cause mortality as well as individual components of the combined efficacy endpoint will also be ascertained. TREAT is an international randomized controlled trial comparing ticagrelor with clopidogrel in STEMI patients treated with fibrinolytic therapy. The results of this trial will inform clinical practice and international guidelines.