CHADDS FORD, PA., and DANBURY, CT--(Marketwire - October 03, 2007) - Endo Pharmaceuticals Holdings Inc. (NASDAQ: ENDP) and Penwest Pharmaceuticals Co. (NASDAQ: PPCO) announced today that they have received a notice from IMPAX Laboratories, Inc. advising of the filing by IMPAX of an Abbreviated New Drug Application (ANDA) containing a Paragraph IV certification under 21 U.S.C. § 355(j) for oxymorphone hydrochloride extended-release tablets CII. This Paragraph IV certification notice refers to Penwest’s U.S. Patent No. 7,276,250, which covers the formulation of OPANA® ER. In addition to U.S. Patent No. 7,276,250, OPANA ER has a new dosage form (NDA) exclusivity that prevents final approval of any ANDA by the FDA until the exclusivity expires on June 22, 2009.
