Endo Pharmaceuticals and Penwest Pharmaceuticals manufacture and market Opana ER for the treatment of moderate to severe pain.
Impax’s submission includes a paragraph IV certification stating the company believes its product does not infringe US patent nos. 7,276,250, 5,662,933 and 5,958,456 or that the patents are invalid or unenforceable. The suit alleges infringement of US patent nos. 5,662,933 and 5,958,456. It also seeks declaratory judgment that the court declare Impax paragraph IV certification notices served on Endo and Penwest as null and void and are of no legal effect and therefore, the court has no subject matter jurisdiction over the patent infringement claims.
Larry Hsu, president and CEO of Impax Laboratories, said: “We believe that our paragraph IV certification for generic Opana ER was proper, that our product does not infringe any valid, enforceable patent, and, as such, we will vigorously defend this lawsuit. Furthermore, we believe that the rescission of our abbreviated new drug application (ANDA) by the FDA was inappropriate and we are continuing to work with the FDA to allow our ANDA to stand.”