Guilford Pharmaceuticals Inc has acquired from Merck & Co. Inc the rights to Aggrastat Injection (tirofiban hydrochloride) in the United States and its territories (Puerto Rico, Virgin Islands, and Guam) for all platelet-mediated cardiovascular diseases, including coronary artery, cerebrovascular and peripheral vascular diseases. Launched in the United States in 1998, Aggrastat is currently available in 82 countries worldwide and will continue to be marketed by Merck in all countries outside the United States and its territories.

Aggrastat, a glycoprotein GP IIb/IIIa receptor antagonist, is used for the treatment of acute coronary syndrome (ACS) including unstable angina, which is characterized by chest pain when one is at rest, and non-Q-wave myocardial infarction (MI). In these patients, Aggrastat reduces the risk of heart attacks by 47 percent within the first seven days and 30 percent within the first month. Aggrastat may also be used to treat these patients prior to undergoing angioplasty, a procedure to open the blockages in the arteries supplying blood to the heart muscle.

Guilford purchased the U.S. rights to Aggrastat for $84 million and has agreed to make certain royalty payments to Merck based on net sales until December 2012. Guilford and Merck have entered into an exclusive supply agreement in which Merck will continue to manufacture and supply the Active Pharmaceutical Ingredient (API) to Guilford through 2014. Additionally, Guilford and Merck have formed a committee to align and leverage the commercial and clinical efforts for Aggrastat worldwide. As part of the agreement, Guilford has also agreed to make commercially reasonable efforts to expand the label for Aggrastat in the United States through the pursuit of a percutaneous coronary intervention (PCI) indication.