Office upholds Pfizer's Lipitor patent

Pfizer is breathing a big sigh of relief. The U.S. Patent & Trademark Office has said it will confirm the drugmaker's basic patent on the blockbuster Lipitor drug. The office had been re-examining the patent in response to a request by Indian generics maker Ranbaxy Laboratories.

It's been a long road for Pfizer, fighting Ranbaxy's patent challenges on Lipitor. The company has grappled with the generics maker in multiple U.S. court cases over Lipitor--and won. This patent confirmation finally appears to shut the book on Ranbaxy's challenges, in the U.S. at least. Until March 2010, when that patent actually will expire.

Ranbaxy has been more successful with its Lipitor challenges in other countries. It prevailed in Norway, and in Canada it and other generics makers defeated Pfizer at the lower court level (Pfizer appealed). But Pfizer's biggest Lipitor challenge actually isn't in any court--it's Zocor, the now-generic statin. Generic-switching has been eating into Lipitor's sales; they dropped by 13.6 percent year-over-year through April 18.

- see the brief in BusinessWeek
- check out Motley Fool's take
- read CNN Money's assessment of Lipitor sales