Memantine hydrochloride (Namenda): USPTO Issues Notice of Final Determination for Patent Term Extension, Generic Launch Delayed

Innovator Forest Lab and Merz Pharma announced (in a press release here) that the U.S. Patent and Trademark Office has issued a Notice of Final Determination granting the full five years of patent term extension for US5,061,703 (the '703 Patent), which is listed in the U.S. Food and Drug Administration Orange Book for NAMENDA(R) (Memantine hydrochloride). The said patent covers a method for the prevention or treatment of cerebral ischemia comprising the step of administering, to a patient in need thereof, an effective amount of Memantine.
Forest has an exclusive license to the '703 patent from the German pharmaceutical company Merz Pharma. Forest and Merz have commenced patent litigation against several generic manufacturers ( as reported by us Here, Here and Here) who have filed ANDAs seeking FDA approval to market generic versions of NAMENDA. A trial in this litigation, pending in the U. S. District Court for the District of Delaware, is scheduled for April 2010. After review of the regulatory timeline for approval of NAMENDA(R) the U.S. Patent and Trademark Office determined that the '703 Patent is entitled to the full five years of patent term extension and will expire on April 11, 2015 (instead of as originally anticipated on September 13, 2013), accordingly, generic launch will be delayed.
The earlier Orange Book expiry for this product was April, 2010. Now, generic launch would be delayed for 5 years.