Pfizer wins US patent battle with Ranbaxy over fluconazole

A US federal court has upheld Pfizer's marketing exclusivity for its antifungal agent Diflucan (fluconazole), keeping a generic version by Indian drugmaker Ranbaxy Laboratories off the market until July 29.

Ranbaxy said it will launch a generic version of the product in July, once Pfizer's patent expires. The Hindustan Times has reported that the US District Court in Washington DC ruled that the six-month exclusivity awarded to Pfizer for testing the drug for pediatric use was valid and that Ranbaxy could not sell its cheaper generic version in the USA until that period runs out.

Diflucan had sales of $1.2 billion last year. A previous patent infringement law suit brought by Pfizer against Ranbaxy was terminated on January 29, when the original patent expired.