Barr Laboratories, Inc said that it has initiated a challenge of the patents listed for Novartis A G's drug Focalin XR (dexmethylphenidate hydrochloride) extended-release capsules, 5mg, 10mg, 15mg & 20mg.

Focalin XR, manufactured for the US by Elan Holdings Inc, is indicated for the treatment of attention deficit hyperactivity disorder (ADHD) in patients aged 6 years and older.

Barr filed an Abbreviated New Drug Application (ANDA) containing a paragraph IV certification with the US Food and Drug Administration (FDA) to market a generic version of Focalin XR in June 2007. The application was accepted in October 2007 and Elan Corporation filed suit against Barr on November 16, 2007 to prevent Barr from marketing the generic product. This action formally initiates the patent challenge process under the Hatch-Waxman Act.

Focalin XR (dexmethylphenidate hydrochloride) extended-release capsules had sales of approximately $252 million in the US, based on IMS sales data ending September 2007.

Barr Pharmaceuticals, Inc. is a global specialty pharmaceutical company that operates in more than 30 countries worldwide and is engaged in the development, manufacture and marketing of generic and proprietary pharmaceuticals, biopharmaceuticals and active pharmaceutical ingredients. A holding company, Barr operates through its principal subsidiaries: Barr Laboratories, Inc., Duramed Pharmaceuticals, Inc. and PLIVA d.d. and its subsidiaries. The Barr Group of companies markets more than 115 generic and 25 proprietary products in the US and more than 1,200 products globally outside of the US.