Barr Laboratories, Inc., a subsidiary of Barr Pharmaceuticals, Inc. confirmed that it is challenging the patents protecting Savient Pharmaceuticals, Inc.'s Oxandrin (oxandrolone tablets, USP) CIII. The company indicated it believes it is the first to file an Abbreviated New Drug Application (ANDA) with the US Food & Drug Administration (FDA) for the product.

Oxandrin (oxandrolone tablets, USP) is indicated as adjunctive therapy to promote weight gain after weight loss following extensive surgery, chronic infections, or severe trauma, and in some patients who without definite pathophysiologic reasons fail to gain or to maintain normal weight, to offset the protein catabolism associated with prolonged administration of corticosteroids, and for the relief of the bone pain frequently accompanying osteoporosis. The product had annual sales of approximately $62 million for the twelve months ended July 2006, based on IMS sales data.

Barr filed its ANDA containing a paragraph IV certification for a generic Oxandrin product with the FDA in June 2006, and received notification of the application's acceptance for filing in August 2006. Following receipt of the notice from the FDA, Barr notified Savient, the patent owner and New Drug Applications (NDA) holder. On September 26, 2006, Savient announced it had filed suit in US District Court of New Jersey to prevent Barr from proceeding with the commercialization of its product. This action formally initiates the patent challenge process under the Hatch-Waxman Act.

Barr Pharmaceuticals, Inc. is a holding company whose principal subsidiaries, Barr Laboratories, Inc. and Duramed Pharmaceuticals, Inc., develop, manufacture and market generic and proprietary pharmaceuticals.