Pfizer wins Viagra patent case against Teva

A federal court has backed Pfizer's claim that one of its Viagra patents doesn't expire until October 2019, meaning that Teva Pharmaceuticals can't move forward with its generic copy of the blockbuster ED drug. "Teva has not shown by clear and convincing evidence that the patent is invalid," U.S. District Judge Rebecca Beach Smith ruled in the opinion, according to Bloomberg. The generic drugmaker had planned to start selling a knock-off version of the Viagra next year after one of Pfizer's core patents expired.

How big of a difference could seven more years of exclusivity make for Pfizer? In June a Leerink Swann analyst told the Wall Street Journal that extended exclusivity could raise the company's earnings by 3% annually between 2013 and 2018. And Pfizer could use all the help it can get as it faces generic competition for Lipitor, the world's best-selling drug, in the coming years.

Teva can still appeal the federal court's, though the company didn't release a statement about its future plans for the case. Other generic drug companies are also challenging the same patent targeted by Teva, but other trials have yet to be scheduled.

"We are pleased that the court recognized the validity and enforceability of our Viagra patent for the treatment of erectile dysfunction," noted vice president and general Amy Schulman in a release. "Protecting the intellectual property rights of our innovative core is critical, and Friday's court decision acknowledges Teva's clear violation of our patent rights."

- see Pfizer's release on the ruling
- read more from the Wall Street Journal
- check out the Bloomberg article