Watson Pharmaceuticals, Inc. today confirmed that its subsidiary, Watson Laboratories, Inc., filed an Abbreviated New Drug Application (ANDA) with the U.S. Food and Drug Administration (FDA) seeking approval to market Levalbuterol Tartrate Inhalation Aerosol,0.045 mg/actuation. Watson’s ANDA product is a generic version of Sunovion Pharmaceuticals, Inc.’s Xopenox HFA which is indicated for the treatment or prevention of bronchospasm in adults, adolescents, and children 4 years of age and older with reversible obstructive airway disease.

Sunovion Pharmaceuticals, Inc. filed suit against Watson on July 27, 2012 in the United States District Court for the District of Delaware seeking to prevent Watson from commercializing its ANDA product prior to the expiration of certain U.S. patents.  The lawsuit was filed under the provisions of the Hatch-Waxman Act, resulting in a stay of final FDA approval of Watson’s ANDA for up to 30 months from the date the plaintiffs received notice of Watson’s ANDA filing or until final resolution of the matter before the court, whichever occurs sooner, subject to any other exclusivities.

Based on available information, Watson believes it may be a “first applicant” to file an ANDA for the generic version of Xopenox HFA and, should its ANDA be approved, may be entitled to 180 days of generic market exclusivity.

For the twelve months ending March 31, 2012, Xopenox HFA had total U.S. sales of approximately $148 million according to IMS Health data.