Barr has filed its abbreviated new drug application (ANDA) containing a paragraph IV certification for a generic Fentora product with the FDA in February 2008. Following receipt of the notice from the FDA that Barr’s ANDA had been accepted for filing, Barr notified the new drug application and patent holder.
On July 22, 2008, Cephalon and Cima Labs filed suit in the US District Court of Delaware to prevent Barr from proceeding with the commercialization of its product. This action formally initiates the patent challenge process under the Hatch-Waxman Act.