Sepracor Inc. has been notified by the US Food and Drug Administration an abbreviated new drug application (ANDA) from Dey, L.P. for a generic version of levalbuterol hydrochloride inhalation solution. Dey's submission includes a Paragraph IV certification alleging that Sepracor's patents listed in the Orange Book for Xopenex inhalation solution are invalid, unenforceable or not infringed by Dey's proposed product. Sepracor announced in September 2005 that the FDA had received an ANDA from Breath Limited for levalbuterol hydrochloride inhalation solution.

Sepracor owns five US patents on methods of treating patients with levalbuterol, with patent terms expiring between 2010 and 2013. Sepracor's sixth patent covering stable levalbuterol formulations expires in 2021. Sepracor believes that its patent position for Xopenex is strong and the company is prepared to vigorously defend its patent rights.

Sepracor Inc. is a research-based pharmaceutical company that discovers, develops and commercialises innovative pharmaceutical products that are directed toward serving unmet medical needs.