Watson Confirms Cenestin(R) Patent Challenge
Watson Pharmaceuticals, Inc. has confimed that its subsidiary, Watson Laboratories, Inc., a Nevada Corporation, has been sued by Teva Women's Health, Inc., in connection with the filing of Watson's Abbreviated New Drug Application (ANDA) for synthetic conjugated estrogens, A, in the 0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg and 1.25 mg tablet strengths. Watson's ANDA is for the generic equivalent of Teva's Cenestin®. The suit was filed on April 23, 2010, in the United States District Court for the District of New Jersey.
Pursuant to the Hatch-Waxman Act, Watson previously notified Teva Women's Health that Watson's ANDA contains a paragraph IV certification asserting that U.S. Patent No. 5,908,638 is invalid, unenforceable and/or will not be infringed by the commercial manufacture, use or sale of the drug products described in Watson's ANDA.
Cenestin® (synthetic conjugated estrogens, A) Tablets are for use by women after menopause to reduce hot flashes and treat dryness, itching, and burning in and around the vagina. For the twelve months ending December 31, 2009, Cenestin® had total U.S. sales of approximately $35 million according to IMS Health data.