The lawsuit is in response to Actavis’s notice to Endo and Penwest, announced on February 15, 2008, advising of the filing by Actavis of an ANDA containing a paragraph IV certification under 21 USC 355(j) for oxymorphone hydrochloride extended-release tablets CII.
Actavis’s Paragraph IV certification notice refers to four Penwest patents listed in the FDA’s Orange Book, which patents cover the formulation of Opana ER. The complaint filed alleges infringement of the US patent, which is one of these Orange Book-listed patents.
Opana ER has been granted new dosage form regulatory exclusivity that prevents the FDA from approving any ANDA for a generic version of Opana ER for launch prior to June 22, 2009, the date such regulatory exclusivity expires.