Inclusion Criteria:  Age ≥ 18 years  Anterior STEMI, based on:  Symptoms of myocardial ischemia (such as chest pain, shortness of breath, jaw pain, arm pain, diaphoresis, or any anginal equivalent) and  ECG criteria:  men > 40 years: ≥ 2 mm of ST elevation in V2 and V3 men ≤ 40 years: ≥ 2.5 mm of ST elevation in V2 and V3 women ≥ 1.5 mm of ST elevation in V2 and V3 Planned primary PCI to occur ≤ 6 hours of onset of first symptoms of myocardial ischemia Institutional Review Board (IRB) / Independent Ethics Committee (IEC) approved consent obtained for study participation  Exclusion Criteria:  Life expectancy of less than 1 year due to non-cardiac pathology Known thyroid disease or thyroid disorder, including subjects on thyroid hormone replacement therapy at the time of randomization Known allergy to iodine Renal disease requiring dialysis Women who are pregnant or breastfeeding. Women of reproductive potential must have a negative pregnancy test prior to randomization Body weight > 140 kg (or 309 lbs) Use of thrombolytic therapy as treatment for the index STEMI event Use of investigational drugs or devices 30 days prior to randomization Any clinically significant abnormality identified prior to randomization that in the judgment of the Investigator or Sponsor would preclude safe completion of the study, or confound the anticipated benefit of FDY-5301