EMBRACE STEMI study: a Phase 2a trial to evaluate the safety, tolerability, and efficacy of intravenous MTP-131 on reperfusion injury in patients undergoing primary percutaneous coronary intervention

Among patients with ST-elevation myocardial infarction (STEMI), reperfusion injury contributes to additional myocardial damage. MTP-131 is a cell-permeable peptide that preserves the integrity of cardiolipin, enhances mitochondrial energetics, and improves myocyte survival during reperfusion. EMBRACE STEMI is a multicentre, randomized, double-blind Phase 2a trial that evaluated the efficacy and safety of MTP-131 vs. placebo infused at a rate of 0.05 mg/kg/h for 1 h among first-time anterior STEMI subjects undergoing primary percutaneous coronary intervention (PCI) for a proximal or mid left anterior descending (LAD) artery occlusion. Administration of MTP-131 was not associated with a significant reduction in the primary endpoint, infarct size by creatine kinase-myocardial band (CK-MB) area under the curve (AUC) over 72 h (5785 ± 426 ng h/mL in placebo vs. 5570 ± 486 ng h/mL in MTP-131; ITALIC! P = NS). MTP-131 was not associated with an improvement in pre-specified magnetic resonance imaging, angiographic, electrocardiographic, or clinical outcomes. Among subjects with first-time anterior STEMI due to a proximal or mid LAD lesion who undergo successful PCI, administration of MTP-131 was safe and well tolerated. Treatment with MTP-131 was not associated with a decrease in myocardial infarct size as assessed by AUC0-72 of CK-MB.