New Therapeutic Approach Did Not Reduce Scarring After Angioplasty

A drug designed to reduce tissue damage to the heart by targeting mitochondria in the cells did not work as researchers hoped for in a study presented Sunday at the 64^th Annual Scientific Session of the American College of Cardiology, meeting March 14-16, 2015, in San Diego, California.

Patients who received Bendavia before undergoing a procedure to clear blocked arteries after a heart attack, either angioplasty or stent, showed no significant reduction in scarring compared with patients receiving placebo, according to results of the EMBRACE-STEMI study. Results were presented at the first late-breaking session by C. Michael Gibson, MD, professor of medicine at Harvard and the study’s lead author.

Among patients with STEMI (ST elevation myocardial infarction) injuries result when blood returns to the area that has been temporarily deprived of oxygen. The process causes the heart to pump blood even harder, and this can result in further heart injury. The study drug, Bendavia, is a cell-permeable peptide designed to target cardiolipin, which is found in the inner mitochondrial membrane, to promote improved mitochondrial response during the process, and limiting the damaging effects of oxygen’s sudden return to the tissue.

The study involved 297 first-time STEMI patients who were randomized to receive the drug (0.05 mg/kg/hr) or blinded placebo more than 15 minutes before a procedure to clear arteries. Patients receiving Bendavia showed a 10% reduction in scarring during the first 3 days after surgery as measured by the levels of an enzyme called creatinine kinase-MB, the study’s primary endpoint. However, this difference was not statistically significant. The results also suggested a trend toward improved heart pumping function during the 8 hours after patients received the drug, but that trend also did not reach statistical significance.

“Our study found that the drug did not prevent irreversible injury to the heart,” Gibson said. However, the apparent sign that the drug reduced new onset heart failure in the first hours after infusion may be a sign that Bendavia improves the heart pumping function and will be the subject of additional study, he said. The study’s chief limitation was the small number of patients.

The trial was funded by Bendavia’s developer, Stealth BioTherapeutics.