Watson Pharmaceuticals, Inc, a leading specialty pharmaceutical company, said its subsidiary Watson Laboratories, Inc. has filed an Abbreviated New Drug Application (ANDA) with the US Food and Drug Administration (FDA) seeking approval to market its Fentanyl Buccal tablets C-II product prior to the expiration of patents owned by Cephalon, Inc.

Watson's Fentanyl Buccal tablets C-II product is a generic version of Cephalon's Fentora C-II (fentanyl buccal tablet) which is indicated only for the treatment of breakthrough pain in opioid tolerant patients with cancer.

In its Notice Letter to Cephalon, Watson contends that US. Patent Numbers 6,200,604 and 6,974,590 are invalid, unenforceable and/or will not be infringed by Watson's manufacture, use or sale of the product described in its ANDA. Based on available information, Watson believes it may be the first applicant to file an ANDA for Fentora containing a paragraph IV certification under the provisions of the Hatch-Waxman Act and, should its product be approved, may be entitled to 180 days of generic market exclusivity.