Appeals court won't rehear Plavix patent ruling

WASHINGTON (Reuters) - A U.S. appeals court on Friday refused to reconsider a ruling that bars Apotex Inc. from selling its generic version of the anticlotting drug Plavix while the company fights a patent lawsuit with the branded drug's maker, Sanofi-Aventis.

Without comment, the U.S. Court of Appeals for the Federal Circuit turned down a petition to rehear its December 8 ruling, which prevents Apotex from selling any more of its product in the United States.

In the earlier ruling, the appeals panel concluded that a federal judge in Manhattan did not abuse his discretion and agreed with his determination that Apotex had failed to raise substantial questions about whether the patents at issue were valid or enforceable.

Plavix, used to prevent blood clots that can trigger heart attacks, was the world's second-biggest-selling medicine with annual sales of about $6 billion before the generic version arrived.

French drug maker Sanofi-Aventis sells Plavix in partnership with Bristol-Myers Squibb Co..

Apotex, a privately-held Canadian drug maker, launched its generic version on August 8, far sooner than analysts had expected, after the failure of a settlement deal with Bristol-Myers and Sanofi that would have delayed generics until 2011.

The defunct agreement is now under criminal investigation by the U.S. government for possible antitrust violations.