CHADDS FORD, PA and DANBURY, CT--(Marketwire - January 25, 2008) - Endo Pharmaceuticals Inc., a subsidiary of Endo Pharmaceuticals Holdings Inc. (NASDAQ: ENDP), and Penwest Pharmaceuticals Co. (NASDAQ: PPCO) announced today that they have filed a lawsuit against IMPAX Laboratories, Inc. in the United States District Court for the District of Delaware in connection with IMPAX’s Abbreviated New Drug Application (ANDA) for OPANA® ER (oxymorphone HCl) extended-release tablets CII.
