Barr to challenge Anesta over AMRIX (cyclobenzaprine)

MarketWatch: Barr Pharmaceuticals, Inc. (of Montvale, NJ) on Nov. 26 confirmed that its subsidiary, Barr Laboratories, Inc., has initiated a challenge of the patent listed by Anesta in connection with its Amrix(R) (cyclobenzaprine hydrochloride) extended-release capsules, 15mg and 30mg.

This is through a lawsuit. MarketWatch noted: On November 26, 2008, Eurand, Inc., Cephalon, Inc., and Anesta AG filed suit in the U.S. District Court for the District of Delaware to prevent Barr from proceeding with the commercialization of its product. This action formally initiates the patent challenge process under the Hatch-Waxman Act.

**UPDATE. 1 Dec 08-->from PRNewswire:

Mylan Inc. today [Dec. 1] confirmed that the company and its subsidiary, Mylan Pharmaceuticals Inc., have been sued by Cephalon Inc., Eurand Inc. and Anesta AG in connection with the filing of an Abbreviated New Drug Application (ANDA) for Cyclobenzaprine Hydrochloride (HCl) Extended-release (ER) Capsules, 15 mg and 30 mg, the generic version of AMRIX(R) Capsules.

Mylan believes it is the first company to have filed a substantially complete ANDA containing a Paragraph IV certification for the product and expects to be awarded 180 days of sole marketing exclusivity once final approval is obtained. Mylan filed its ANDA with the U.S. Food and Drug Administration (FDA) in August. Cephalon, Eurand and Anesta filed a lawsuit Nov. 26 in the U.S. District Court for the District of Delaware alleging infringement of U.S. Patent No. 7,387,793.