DURHAM, NC – A novel drug designed to lessen muscle damage from a heart attack has passed initial safety tests at the Duke Clinical Research Institute. Results of the study, available online and to be published in the February 19 issue of the journal Circulation, reflect the first time the drug has been tested in humans. The drug, known as KAI-9803, blocks the activity of an enzyme called delta protein kinase C that triggers cell and tissue death in the aftermath of percutaneous coronary intervention, or PCI. PCI is a set of procedures including balloon angioplasty and stent placement that clear and prop open clogged coronary blood vessels that lead to a heart attack – a process known as reperfusion.