UPDATE 1-Lawyers spar as Plavix patent trial begins

(Adds details, quotes, analyst report)

By Martha Graybow

NEW YORK, Jan 22 (Reuters) - A lawyer for Sanofi-Aventis (SASY.PA) and Bristol-Myers Squibb Co. (BMY.N) urged a U.S. judge to uphold the patent on blockbuster anti-clotting medication Plavix on Monday, as a high-stakes trial over the drug's future got under way.

Sanofi and Bristol-Myers are trying to protect Plavix from competition with a cheaper version made by generic drug maker Apotex Inc., a privately held Canadian company that sold its copycat drug in the United States briefly last year before the U.S. court stopped the shipments.

In opening arguments in U.S. District Court in Manhattan, Evan Chesler, a lawyer for Sanofi and Bristol-Myers, said Apotex had no legal basis for its argument that the Plavix patent should be invalidated.

"They have basically rewritten history," he said, arguing before District Judge Sidney Stein, who is hearing the case without a jury.

But Apotex lawyer Robert Breisblatt said the patent should not be allowed to stand, in part because the formula for the drug would have been "obvious" to scientists in the field.

"It is invalid because it is obvious," he said in his opening statement.

Apotex has been challenging the patent since 2002, arguing that it is not truly innovative but is based on another patent that expired in 2003 and that provided information on how to make clopidogrel bisulfate, Plavix's chemical name.

Breisblatt said the information in that expired patent was like "a neon highway" that other scientists could follow, and that Plavix therefore should not be a patent-protected drug.

New York-based Bristol-Myers sells Plavix in the United States for Sanofi, which is based in Paris.

Plavix had annual sales of $6 billion before the Apotex copy hit the U.S. market. The drug is Bristol-Myers' biggest-selling medicine. Sales of the generic have posed a serious threat to Bristol-Myers' earnings.

Apotex launched its copy of the drug last August, far sooner than industry experts 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 investigation by the U.S. government for possible antitrust violations.

Huge supplies of the generic version were delivered by Apotex in the days before a court injunction halted the shipments. Those supplies remain on the market.

Many pharmaceutical analysts have predicted Sanofi and Bristol will prevail in the patent-infringement trial, in large part because Judge Stein previously granted a preliminary injunction in their favor.