Astellas Launches New Stress Agent for Radionuclide MPI

June 25, 2008 - Lexiscan (regadenoson) injection, an A2A adenosine receptor agonist, for use as a pharmacologic stress agent in radionuclide MPI in patients unable to undergo adequate exercise stress, is now commercially available, reported Astellas Pharma U.S. Lexiscan, co-developed with CV Therapeutics, is the first A2A adenosine receptor agonist shown to be safe and effective as a pharmacologic stress agent in MPI studies. The A2A adenosine receptor subtype is primarily responsible for coronary vasodilation. "Our clinical experience shows that an increasing number of patients are requiring pharmacologic stress agents for MPI studies," said Gregory Thomas, M.D., clinical aassociate professor of medicine and director of nuclear cardiology education at the University of California at Irvine School of Medicine. MPI tests, commonly called cardiac stress tests, identify areas of poor blood flow in the heart to determine the extent of coronary artery disease, a condition that affects 16 million Americans and is responsible for more than 450,000 deaths annually in the United States. Many patients exercise on a treadmill to generate the increase in coronary blood flow necessary to perform an MPI study. However, almost half of patients undergoing cardiac stress tests each year are unable to exercise adequately because of medical conditions. For these patients, a pharmacologic stress agent that temporarily increases blood flow through the coronary arteries is used to mimic the increase in coronary blood flow caused by exercise. About 7.5 to 9.3 million MPI studies were performed last year in the U.S. In two identically designed Phase III clinical trials, Lexiscan met primary endpoints for scan agreement rates by showing with 95 percent confidence that MPI studies conducted with Lexiscan were similar to MPI studies conducted with Adenoscan (adenosine injection). Lexiscan was generally well-tolerated in both Phase III studies. The most common adverse events reported in patients who received Lexiscan were shortness of breath, headache, flushing, chest discomfort, angina or ST-segment depression, dizziness and nausea. For more information: www.Lexiscan.com