Sepracor, Inc. Drug Lunesta Fails in Anxiety Trial

MARLBOROUGH, Mass. - (Business Wire) Sepracor Inc. (Nasdaq: SEPR) today announced that it has completed the analysis and validation of the preliminary results of a Phase II, 440-patient study evaluating the efficacy and safety of SEP-225441, a modified-release formulation of eszopiclone for the treatment of generalized anxiety disorder (GAD). Sepracor determined that the study did not meet its primary efficacy endpoint, which was reduction in symptoms of GAD, as assessed using the clinician-rated HAM-A scale (Hamilton Anxiety Rating Scale, a standard scale used to assess anxiety in clinical trials and consisting of a list of symptoms commonly associated with anxiety).

“While we are disappointed with the preliminary analysis of the study results, we are in the process of further analyzing the data in an effort to determine whether any of the secondary endpoints were met and whether this compound warrants further clinical development,” said Mark H.N. Corrigan, M.D., Executive Vice President, Research and Development of Sepracor.

About Sepracor

Sepracor Inc. is a research-based pharmaceutical company dedicated to treating and preventing human disease by discovering, developing and commercializing innovative pharmaceutical products that are directed toward serving large and growing markets and unmet medical needs. Sepracor's drug development program has yielded a portfolio of pharmaceutical products and candidates with a focus on respiratory and central nervous system disorders. Currently marketed products include LUNESTA® brand eszopiclone, XOPENEX® brand levalbuterol HCl Inhalation Solution, XOPENEX HFA® brand levalbuterol tartrate Inhalation Aerosol, BROVANA® brand arformoterol tartrate Inhalation Solution, OMNARIS™ brand ciclesonide Nasal Spray and ALVESCO® brand ciclesonide HFA Inhalation Aerosol. Sepracor's corporate headquarters are located in Marlborough, Massachusetts.

LUNESTA, XOPENEX, XOPENEX HFA and BROVANA are registered trademarks of Sepracor Inc. OMNARIS is a trademark and ALVESCO is a registered trademark of Nycomed GmbH.

For a copy of this release or any recent release, visit Sepracor’s web site at www.sepracor.com.

Sepracor Inc. Jonaé R. Barnes, 508-481-6700 Sr. Vice President, Investor Relations and Corporate Communications