A phase 3 clinical trial will begin later this year to compare the effects of prasugrel (CS-747), an investigational antiplatelet agent, with the antiplatelet market leader Plavix, in patients undergoing a procedure to open clogged arteries.

The study, TRITON-TIMI 38, will include 13,000 patients worldwide with acute coronary syndrome (heart attacks and/or unstable angina), who are to undergo percutaneous coronary intervention (PCI), a procedure to open a clogged heart artery. Approximately 850 hospitals in 25 countries are targeted for participation in this study.

Prasugrel is being developed by Eli Lilly and Company and Tokyo-based Sankyo Company, Ltd. for the treatment of patients who have suffered a heart attack or heart-related chest pain.

The primary focus of the study is to compare the agents' ability to prevent heart attack, stroke and death in patients who undergo PCI. The secondary focus will be to look at the impact on bleeding, recurrent heart-related chest pain (ischemia) or the need for additional procedures to restore blood flow (urgent target revascularization).

"This is an exciting trial that hopefully will give us the opportunity to make an advancement in the treatment of cardiovascular disease," Bernhardt Zeiher, medical director of the prasugrel product team for Lilly said adding, "Given the prevalence of heart disease around the world, the lives of many patients could be affected."

Fred Senatore, Sankyo's executive director of clinical development said, "Together we hope to develop an agent that can make a difference in the lives of patients with acute coronary syndrome who are undergoing PCI."

Prasugrel is an investigational oral antiplatelet agent designed to prevent platelet activation by blocking adenosine diphosphate receptors on the platelet surface. The novel oral compound was discovered by Sankyo and Ube industries Ltd. It is being investigated for the treatment of patients with acute coronary syndrome who undergo percutaneous coronary intervention.

The study will be conducted by Lilly and Sankyo in conjunction with the TIMI Study Group, led by Eugene Braunwald, at Harvard Medical School and Brigham and Women's Hospital in Boston, Mass.