LUNESTA(R) Next-Day Function and Discontinuation Data from a Long-Term 12-Week Study in Elderly Patients Presented at ECNP

Sepracor Inc. (Nasdaq: SEPR) today announced the presentation of LUNESTA^® brand eszopiclone Phase IV study data at the 21^st European College of Neuropsychopharmacology (ECNP) Congress in Barcelona. The poster presentations reflected results from a 12-week, double-blind, randomized safety and efficacy study of 388 elderly patients (65-85 years of age) who were administered either LUNESTA 2 mg or placebo nightly. Upon conclusion of the 12-week, double-blind treatment period, all patients received single-blind placebo for two weeks to assess rebound and withdrawal effects. This two-week, single-blind period was then followed by an additional two-week evaluation period in which patients received neither LUNESTA nor placebo in order to assess the durability of the response.

A 12-Week Study of Eszopiclone in Elderly Out-patients With Primary Insomnia: Effects of Treatment Discontinuation

In this study, sleep latency, wake time after sleep onset and total sleep time were all statistically significantly (p=0.01) improved compared to baseline measures following discontinuation of LUNESTA treatment, indicating absence of rebound insomnia (defined as a worsening of sleep relative to pretreatment levels). Twelve weeks of nightly LUNESTA administration were not followed by withdrawal symptoms after discontinuation. Key findings from the study included:

• No statistically significant difference in Benzodiazepine Withdrawal Symptoms Questionnaire (BWSQ; an assessment of symptoms associated with benzodiazepine discontinuation) scores for LUNESTA-treated patients at the end of the double-blind treatment period (Week 12) relative to the end of the single-blind placebo administration period (Week 14). At Week 14, the BWSQ scores for patients treated with LUNESTA during the initial 12-week period were comparable to those who received placebo throughout the study duration; and
• The percentages of patients taking LUNESTA with "no insomnia” and "sub-threshold insomnia”, as measured by the Insomnia Severity Index (ISI; a measure of patients’ perception of insomnia), declined from the end of the double-blind period to the end of the 4-week follow-up period. However, despite this decline, the percentages of patients in these categories were still higher at the end of the 4-week follow-up period than they were at baseline, prior to the start of LUNESTA therapy.

The Efficacy of 12 Weeks of Eszopiclone Treatment in Elderly Patients With Primary Insomnia: Effect on Daytime Function

Electronic diaries, which were completed at the end of each day, captured patient-reported measures of daytime ability to function and duration and number of naps. Daytime function was assessed using an 11-point Likert-type scale, as well as by Insomnia Severity Index (ISI) questionnaires administered at three-week intervals. Quality of life and level of disability were also assessed using the 36-Item Short-Form Health Survey (SF-36) and Sheehan Disability Scale (SDS), respectively.

Patients administered LUNESTA reported significant improvements from baseline in key measures of daytime function versus the placebo group when averaged over the 12-week, double-blind treatment period. These measures included improvements in:

• Daytime alertness (p<0.001) scores
• Ability to function (p<0.001) scores
• Ability to concentrate (p<0.001) scores; and
• Sense of physical well-being (p<0.001) scores.

The abovementioned parameters were also statistically significantly improved versus placebo during the first three weeks of treatment, and these improvements were sustained through the last three weeks of the double-blind period.

Both number of naps and total daily nap time decreased from baseline for subjects who napped for both the LUNESTA and placebo treatment groups, and these decreases were statistically significantly different between the two treatment groups (p=0.0064 for number of naps and p=0.0138 for daily nap time) during the first three weeks of the study but not for the remainder of the study period.

Using the ISI, patients administered LUNESTA reported significant improvements versus the placebo treatment group on several of the extended items that measured next-day function. At Week 12, these statistically significant differences were seen in measures of:

• Improved sleep quality (p<0.0001) scores;
• Improvement in feeling refreshed/rested (p=0.0001) scores;
• Reduced daytime fatigue (p=0.0104) scores; and
• Reduced number of nights per week with sleep difficulties (p=0.0023) scores.

These abovementioned ISI measures, as well as attention/concentration, were also statistically significantly improved for patients taking LUNESTA versus patients administered placebo when averaged over the double-blind treatment period. There were no significant differences from placebo in ISI scores measuring attention, concentration, relationship enjoyment or mood disturbance.

Results of the SF-36 showed that patients administered LUNESTA reported statistically significantly improved general health (p=0.0088) and vitality (p=0.0084) at Week 12 versus patients administered placebo. Patients administered LUNESTA showed general improvements from baseline in the social life and family life/home responsibilities items of the SDS versus patients administered placebo, which were statistically significant when measured at Week 6 (p=0.0154 for social life and p=0.0279 for family life/home responsibilities), but not at Week 12. A numerical difference in scores was seen in the work/school item of the SDS, but this difference was not statistically significant.

Important Information About LUNESTA

LUNESTA is indicated for the treatment of insomnia in patients 18 years of age and older who are experiencing difficulty falling asleep and/or maintaining sleep through the night. LUNESTA is available in 1 mg, 2 mg and 3 mg tablets, and treatment should be individualized based on a patient’s age, medical history and insomnia symptoms. Impaired motor and/or cognitive performance after repeated exposure or unusual sensitivity to sedative/hypnotic drugs is a concern in the treatment of the elderly and/or debilitated patients. The recommended starting dose of LUNESTA for these patients is 1 mg. LUNESTA is a Schedule IV controlled substance.

LUNESTA works quickly and should only be taken immediately before bedtime. Patients should have at least eight hours to devote to sleep before becoming active. Patients should not engage in any activity after taking LUNESTA that requires complete alertness, such as driving a car or operating machinery. Patients should use extreme care when engaging in these activities the morning after taking LUNESTA. Patients should not use alcohol while taking any sleep medicine. Most sleep medicines carry some risk of dependency. As with all sleep medicines, somnambulism (sleepwalking), including eating or driving while not fully awake, with amnesia for the event, has been reported. Additionally, rare cases of severe allergic reactions have been reported. Patients who report these events should discontinue treatment and should not be rechallenged with LUNESTA. Patients should not use sleep medicines for extended periods without first talking to their doctor. Patients should see their doctor if they experience unusual changes in thinking or behavior, or if sleep problems do not improve in 7 to 10 days as this may be due to another medical condition. Side effects may include unpleasant taste, headache, drowsiness and dizziness. For complete prescribing information, please visit the LUNESTA web site at www.lunesta.com, or click here.

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 and OMNARIS™ brand ciclesonide Nasal Spray. 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 of Nycomed GmbH.

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