Sepracor Inc. has entered into a settlement and license agreement with Glenmark Generics Inc., USA, Glenmark Generics Ltd., and Glenmark Pharmaceuticals Ltd. (collectively Glenmark) to resolve a United States patent infringement suit related to Glenmark's filing of an abbreviated new drug application (ANDA) with the US FDA to market generic Eszopiclone tablets, which Sepracor markets under the brand name Lunesta.

Under the terms of the settlement and license agreement, and upon approval and entry of a Consent Judgement and Order of Permanent Injunction by the United States District Court for the District of New Jersey, Glenmark would be permitted to launch its generic product on the later of November 30, 2013, which is two and one half months (2.5 months) prior to the expiry of Sepracor's United States Patent 6,444,673, or May 30, 2014 if Sepracor obtains paediatric exclusivity for Lunesta.

The settlement and license agreement and Consent Judgement and Order also would permit Glenmark to launch its generic product earlier under certain circumstances. The court's approval of the proposed Consent Judgement and Order of Permanent Injunction would dismiss Sepracor's and Glenmark's respective claims and defenses without prejudice in the consolidated litigation currently pending against Glenmark and other defendants.

Lunesta is available in 1mg, 2mg and 3mg tablets and is indicated for the treatment of insomnia. According to IMS Health data for the 12 month period ending March 2010, Lunesta achieved annual sales of USD 741 million and is the second highest selling branded prescription medication in its class.