TG100-115 is able to reduce the size of heart attacks in pre-clinical models. The hypothesis of this study is that TG100-115 can be given safely to patients who suffer a heart attack and undergo angioplasty to restore blood flow. We will also evaluate whether TG100-115 reduces heart muscle damage.

Inclusion Criteria:

• Age 18-80 yrs
• ECG patterns consistent with an acute anterior myocardial infarction with ST segment elevation of 2mm in two contiguous ECG leads among leads V1-V4.
• Have prolonged, continuous (lasting at least 20 mins) signs and symptoms of myocardial ischemia not eliminated with nitrates.
• Intent to proceed to primary PCI within 6 hours of chest pain onset
• Sign an informed consent form and be willing to attend follow-up visits for safety and other study assessments.

Exclusion Criteria:

• Female of childbearing potential.
• History of previous myocardial infarction.
• History of congestive heart failure.
• Requirement for a cardiac pacemaker or defibrillator.
• Cardiogenic shock.
• Patients previously treated with thrombolytic therapy.
• Myocardial ischemia precipitated by a condition other than atherosclerotic coronary artery disease.