Watson submits application to FDA for generic Fentora

CORONA, Calif. Watson Laboratories has submitted an application with the Food and Drug Administration to market a generic version of Cephalon’s cancer pain drug Fentora.

In its application, Watson asserts the ‘604 and ‘590 patents for Fentora (fentanyl buccal tablet) are invalid, unenforceable or will not be infringed by the manufacture, use or sale of the product. Both patents expire in 2019.

Cephalon has a three-year period of marketing exclusivity for Fentora that extends until September 2009. The company said it will review Watson’s notice and has 45 days to file a patent infringement lawsuit.

According to Cephalon, Fentora had sales in 2007 of over $135 million in the U.S.