Direct intramyocardial injection of VEGF mRNA in patients undergoing coronary artery bypass grafting.

Vascular endothelial growth factor A (VEGF-A) has therapeutic cardiovascular effects but delivery challenges have impeded clinical development. We report the first clinical study of naked mRNA encoding VEGF-A (AZD8601) injected into the human heart. EPICCURE (NCT03370887) was a randomized, double-blind study of AZD8601 in patients with left ventricular ejection fraction (LVEF) of 30-50% undergoing elective coronary artery bypass surgery. Thirty epicardial injections of AZD8601 (total 3 mg) or placebo in citrate-buffered saline were targeted to ischemic but viable myocardial regions mapped using quantitative [O]-water positron emission tomography. Seven patients received AZD8601 and four received placebo and were followed for 6 months. There were no deaths or treatment-related serious adverse events, and no AZD8601-associated infections, immune reactions or arrhythmias. Exploratory outcomes indicated potential improvement in LVEF, Kansas City Cardiomyopathy Questionnaire scores and N-terminal pro-B-type natriuretic peptide levels but the study is very limited in size and significant efficacy conclusions are not possible from the data set. Naked mRNA without lipid encapsulation may provide a safe delivery platform for introducing genetic material to cardiac muscle, but further studies are needed to confirm efficacy and safety in a larger patient pool.