Barr Laboratories Inc has received tentative approval from the U.S. Food & Drug Administration (FDA) for its generic version of Kos Pharmaceutical Inc's Niaspan 500 mg and 750 mg Extended-Release Tablets (Niacin Extended-Release Tablet). The Company is currently challenging the validity and/or infringement of certain patents held by Kos for Niaspan 500 mg and 750 mg Extended-Release Tablets and a trial in the Federal District Court in New York is currently scheduled for December 2004.

The Company announced on May 12, 2003 that it had received tentative approval for its generic version of Kos Pharmaceutical Inc's Niaspan 1000 mg Extended-Release Tablets (Niacin Extended-Release Tablet).

In May 2002, Barr received notice from the FDA that its Abbreviated New Drug Application (ANDA) for Niacin 500 mg Extended-Release Tablets had been accepted for filing in March 2002. Barr submitted an amendment to the Company's original application to include Niacin 750 mg Extended-Release Tablets in April 2002. Following receipt of notice from the FDA, Barr notified Kos, who owns the three patents listed for Niaspan. On August 12, 2002, Kos announced that it had filed suit in Federal Court in New York to prevent Barr from proceeding with the commercialization of these products. Barr believes that it is the first to file an application for these products.

Niacian 500 mg and 750 mg Extended-Release Tablets have tentative approval for use as an adjunct to diet and other non-pharmacologic measures for reduction of elevated cholesterols in patients when the response to an appropriate diet and other non-pharmacologic measures has been inadequate. Cases of severe hepatic toxicity have occurred in patients who have substituted extended release tablets for immediate release tablets. Liver disease or patients who use substantial quantities of alcohol may preclude use.

Niaspan 500 mg Extended-Release Tablets had annual sales of approximately $191 million for the twelve months ended April 2003. Niaspan 750 mg Extended-Release Tablets had annual sales of approximately $20 million for the twelve months ended April 2003.