Haug Partners Successfully Defends Firazyr® Patent Against Invalidity and Unenforceability Allegations

June 6, 2018

After a four-day bench trial and extensive post-trial briefing, Judge Gregory M. Sleet of the United States District Court for the District of Delaware issued a decision concluding that the asserted claim of U.S. Patent No. 5,648,333, which is listed in the Orange Book for Shire’s Firazyr® product, is not invalid for obviousness-type double patenting, a conclusion which was supported by a showing of long-felt need and commercial success. The Court also held that prosecution laches does not bar recovery because there was no unreasonable or unexplained delay in prosecution of the ’333 patent. Prosecution laches is an increasingly uncommon defense, making this decision important to the development of this legal doctrine.

Firazyr® is a single-use, prefilled syringe for subcutaneous administration to treat acute attacks of hereditary angioedema in adults 18 years of age and older. We are delighted that we could help Shire and Sanofi-Aventis, the owner of the ’333 patent, achieve this outcome.