Scottish Generic Firm Files Patent Challenge on Sanofi-Aventis' Plavix

French drugmaker sanofi-aventis is facing yet another patent challenge -- this time in Europe -- to its top-selling antistroke drug Plavix.

Aircoat, a Scottish generic firm, has challenged sanofi-aventis' Plavix (clopidogrel bisulfate) patent in a Scottish Court. The UK patent was issued from sanofi-aventis' European patent, the company said.

"Sanofi-aventis believes Aircoat's arguments to be without merit, and will vigorously defend its patent," the company added.

Sanofi-aventis is already facing two patent suits against Plavix in the U.S. Dr. Reddy's and Apotex both filed abbreviated new drug applications in 2002 to market a Plavix equivalent. Sanofi-aventis has filed suit in federal court to block the U.S. patent challenges. The company announced recently that the U.S. case is set to go to trial March 4.