Pfizer’s patent related to calcium salt of atorvastatin, with an expiry date of July 2010, found invalid.
The Federal Court of Canada denied Pfizer’s application to block approval of Ranbaxy’s generic version of Lipitor. The court found Pfizer’s patent covering the calcium salt of atorvastatin, the active ingredient in Lipitor, invalid.
The ruling involved Canadian patent 2,021,546, which is set to expire in July 2010. Separately, the court ruled that Pfizer’s basic patent covering atorvastatin, Canadian patent 1,268,768, would be infringed by Ranbaxy. Thus, the Minister of Health Canada was ordered not to issue a Notice of Compliance until expiry of this patent, which is May 7, 2007.
Ranbaxy reports that The Honorable Justice von Finckenstein found the patent invalid for not, “correctly and fully describing the invention.” Specifically, Justice von Finckenstein found that the, “false suggestion of a ten-fold increase in activity cannot be backed up by the data provided.”
Pfizer says that it will appeal the court’s ruling. “This decision presents clear and substantive issues for appeal,” says Pfizer general counsel Allen Waxman. “We will begin that process immediately in an effort to sustain Lipitor’s exclusivity through July 2010.”