This study will evaluate the potential benefit of blocking inflammation during a heart attack using an investigational anti-inflammatory medicine called SP16. The study will enroll 10 patients and all 10 patients will receive a standard dose of SP16.

The main hypothesis of this study is that a single subcutaneous administration of SP16 0.2 mg/kg is safe and well tolerated in patients with ST segment elevation myocardial infarction (STEMI) and associated with a reduction in the acute inflammatory response to STEMI, as measured as area-under-the-curve (AUC) for C reactive protein (CRP), the preferred inflammatory marker for cardiovascular risk prognostication.

SP16 will be administered subcutaneously as this route has greater ease of administration than intravenous injection. A single dose administration has been selected based upon pre-clinical data and expected clinical use of SP16.

In order to be eligible for this study, patients must meet all the 3 criteria:

1. Presentation to the hospital with acute STEMI defined as chest pain (or equivalent) with an onset within 12 hours and electrocardiogram (ECG) evidence of ST segment elevation (>1 mm) in 2 or more anatomically contiguous leads that is new or presumably new (for intermittent pain lasting more than 12 hours, the time from the when the pain became severe and constant);
2. Coronary intervention planned and/or completed within 12 hours of symptom onset, and enrollment in the study within 6 hours of angiogram (max 18 hours from symptom onset)
3. Age>21 years

In order to be eligible for this study, patients must meet none of the Exclusion criteria.

• Inability to give informed consent
• Hemodynamic instability as defined as need for inotropic or vasoactive agents, or need for mechanical support devices (including intra-aortic balloon pump)
• Pregnancy or breastfeeding
• Preexisting congestive heart failure (American Heart Association/American College of Cardiology class C-D, New York Heart Association III-IV)
• Preexisting severe left ventricular dysfunction (LVEF<20%)
• Preexisting severe valvular heart disease
• Known active infections (acute or chronic)
• Recent (<14 days) or active use of immunosuppressive drugs (including but not limited to high-dose corticosteroids [>1 mg/kg of prednisone equivalent], tumor necrosis factor-alpha blockers, cyclosporine) not including non-steroidal anti-inflammatory drugs (NSAIDs) or corticosteroids used for intravenous (IV) dye allergy only)
• Recent (<14 days) or active use of anti-inflammatory drugs (not including NSAIDs or corticosteroids used for IV dye allergy only)
• Known chronic inflammatory disease (including but not limited to rheumatoid arthritis, systemic lupus erythematosus)
• Known active malignancy of any type, or prior diagnosis in the past 10 years
• Neutropenia (absolute neutrophil count<1,800/mm3 [or <1,000/mm3 in African American patients])
• Severe impairment in renal function (estimated glomerular filtration rate <30 ml/kg*min)
• Anticipated need for cardiac or major surgery
• Known Allergy to SP16

12 months