RALEIGH, N.C.--(BUSINESS WIRE)--May 18, 2006--Salix Pharmaceuticals, Ltd. (NASDAQ:SLXP - News) today announced the issuance of a patent, entitled “Polymorphous Forms of Rifaximin, Processes for Their Production and Use Thereof in the Medicinal Preparations”, by the United States Patent and Trademark Office. This patent, assigned patent number US 7,045,620, is believed to extend the patent coverage of the current form of rifaximin, which we market in the United States under the tradename XIFAXAN®, until May 22, 2024. Alfa Wassermann S.p.A., the patent owner, has licensed rights to rifaximin in the United States to Salix Pharmaceuticals. The patent is a composition of matter and process patent that covers several physical states of XIFAXAN.
