Cephalon sues Watson over Fentora

USA-headquartered Cephalon says that it and its wholly-owned subsidiary Cima Labs have filed a law suit in US District Court in Delaware against Watson Pharmaceuticals, and its affiliate, Watson Laboratories, for infringement of US Patent Nos 6,200,604 and 6,974,590, which cover methods of use for the Cephalon product Fentora (fentanyl buccal tablet) [C-II]. The 6,200,604 and 6,974,590 patents do not expire until 2019. Fentora was approved by the Food and Drug Administration in September 2006 for the management of breakthrough pain in patients with cancer who are already receiving and who are tolerant to opioid therapy for their underlying persistent cancer pain.

The law suit is based upon an Abbreviated New Drug Application filed by Watson seeking FDA approval for a generic equivalent of fentanyl buccal tablets to be sold in the USA. Watson alleges that the above two Fentora patents are invalid, unenforceable and/or will not be infringed by the generics group's manufacture, use or sale of the product described in its ANDA.