HAYWARD, Calif. — Drug maker Impax Labs is looking to challenge the patent protection on a drug used to treat pain related to cancer, the company said Monday.
Impax said it had filed a regulatory approval application with the Food and Drug Administration for a generic version of Cephalon's Fentora (fentanyl) buccal tablets in the 100 mcg, 200 mcg, 400 mcg, 600 mcg and 800 mcg strengths. The drug is used to treat breakthrough cancer pain, defined as pain related to cancer that can't be controlled by other drugs.
Impax's application contained a paragraph IV certification, a legal assertion that one or more patents covering a drug are invalid, unenforceable or won't be infringed. In response, Cephalon and CIMA Labs filed a patent infringement suit against Impax in the U.S. District Court for the District of Delaware, under the terms of the Hatch-Waxman Act of 1984, the law that created an abbreviated approval pathway for generic pharmaceuticals.
Fentora had sales of about $159 million during the 12-month period ended in September, according to Wolters Kluwer Health.