Federal Judge Backs Viagra's Canadian Patent

20 June, 2009

Pfizer Inc., the world's biggest drugmaker, has a valid Canadian patent on the impotence pill Viagra, a federal judge ruled. The judge dismissed a bid by Novopharm Ltd. to introduce a generic version of the drug. Judge Michael Kelen, in a 54-page ruling today, prohibited the Canadian minister of health from approving a generic version of Viagra until New York-based Pfizer's patent expires in 2014.

Novopharm, a unit of Petah Tikva, Israel-based Teva Pharmaceutical Industries Ltd., argued that Pfizer's patent was invalid because it was obvious. Kelen rejected the argument saying it wasn't obvious in 1994, when Pfizer first developed the treatment, that sildenafil, the main ingredient in Viagra, would be effective in treating erectile dysfunction.