Horizon Pharma has announced that it has received a Notice of Allowance from the United States Patent and Trademark Office (USPTO) for the US patent application number 14/596,919 (US publication number 2015-0126607), entitled "Diclofenac Topical Formulation" that covers Horizon's US approved product PENNSAID (diclofenac sodium topical solution) two percent w/w (PENNSAID 2 percent).

This Notice of Allowance concludes the substantive examination of the patent application and will result in the issuance of the US patent after administrative processes are completed. The US patent scheduled to issue from this application will expire in 2027.  After issuance, Horizon plans to list the patent in the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations, or Orange Book. This will be the tenth US patent to be listed in the Orange Book for PENNSAID two percent.

The drug is a non-steroidal anti-inflammatory drug indicated for the treatment of pain of osteoarthritis (OA) of the knees.