Patent fight ends; generic BuSpar goes to market

Medical Marketing and Media, May 2001

Three generic houses are marketing four different dose strengths of buspirone HCI, the generic version of Bristol-Myers Squibb's (BMS) BuSpar. Each has 180-day exclusivity rights, following resolution of a federal court case.

Mylan Laboratories is manufacturing and marketing 15 mg tablets of buspirone with 180 days of exclusivity on this dosage form, since it was the first company to file an ANDA for it. Watson Pharmaceuticals has FDA clearance to launch 5 mg and 10 mg tablets also with the exclusivity period. Watson will sell its version at a 10.5 percent discount, as compared to BuSpar, according to FDC Reports.

Par Pharmaceutical has exclusivity to sell a 7.5 mg dose, which is not marketed by BMS. BuSpar had overall sales of $709 million last year, according to one report.

The marketing jam broke after a suit filed by Mylan was resolved by a Washington, D.C. appeals court. Mylan went to court after BMS filed a patent, with FDA, on a metabolic form of the drug. The patent was filed just 12 hours before the original exclusivity period was about to expire, November 22, 2000.

After arguments, the court, on March 15, ordered the FDA to remove the patent and grant immediate approval to Mylan's product. Bristol-Myers Squibb asked an appeals court for a stay, which was temporarily granted. The court concluded on March 27 that BMS had "not established a likelihood of success on the merits ... ." On the following day, final approval was granted to Mylan's product.