Pfizer targets five internet sites for selling an unapproved copy of Pfizer's top selling cholesterol medicine, Lipitor

The suits were filed in U.S. district courts in Delaware and Connecticut against Generic Lipitors, Online Rx DrugStore, WorldMedsRX, B. M. International, and Offshore Pharma.

Pfizer said the sites market a product called "Storvas," which is advertised as being manufactured by Ranbaxy Pharmaceuticals Inc. of India . The lawsuits seek injunctions against further sales of "Storvas" and claim damages for infringement of Pfizer's patent and trademark rights for Lipitor. The complaints also seek to remove references to Lipitor in advertising materials and to eliminate computer links that misdirect patients to an illegal, unapproved product.

Pfizer filed a similar suit on April 12 against Look4Generics.com in U.S. District Court in Delaware. The company noted that the internet provides easy access to websites that sell unapproved or counterfeit pharmaceutical products that could put patient health at risk.