Watson Pharmaceuticals, Inc. confirmed that its subsidiary, Watson Laboratories, Inc., filed an Abbreviated New Drug Application (ANDA) with the US Food and Drug Administration (FDA) seeking approval to market sildenafil citrate tablets, 25, 50 and 100 mg. Watson's sildenafil citrate tablets are a generic version of Pfizer Inc.'s Viagra, which is indicated for the treatment of erectile dysfunction (ED).

Pfizer filed suit against Watson on June 1, 2011 in the United States District Court for the Southern District of New York seeking to prevent Watson from commercializing its product prior to the expiration of US Patent No. 6,469,012. Pfizer's lawsuit was filed under the provisions of the Hatch-Waxman Act, resulting in a stay of final FDA approval of Watson's ANDA until November 6, 2013 or until final resolution of the matter before the court, whichever occurs sooner, subject to any other exclusivities.

For the twelve months ending April 30, 2011, Viagra had total US sales of just over $1 billion, according to IMS Health data.

Watson Pharmaceuticals, Inc. is an integrated global specialty pharmaceutical company. The company is engaged in the development, manufacturing, marketing and distribution of generic pharmaceuticals and specialized branded pharmaceutical products focused on urology and women's health.