Results of Sepracor's LUNESTA(R) Next-Day Driving Study in Patients with Primary Insomnia Presented at American College of Neuropsychopharmacology Meeting.

MARLBOROUGH, Mass. -- Sepracor Inc. (Nasdaq: SEPR) today announces the presentation of results from a study of LUNESTA([R]) brand eszopiclone that measured the effects on actual next-morning driving ability and other objective assessments of cognitive and psychomotor function. Results from this randomized, double-blind, placebo-controlled, two-way crossover study in patients with primary insomnia will be presented today at the American College of Neuropsychopharmacology annual meeting in Hollywood, Fla. This study is unique in that it was comprised of patients with insomnia who drove automobiles in a controlled environment, in contrast to other driving studies conducted in computer-generated driving simulators.

The primary objective of this study was to assess next-day, actual on-the-road car-driving ability and cognitive and psychomotor performance in patients with primary insomnia administered either LUNESTA 3 mg or placebo the evening before. Next-day driving ability was assessed by brake-reaction time (BRT) in a dual-controlled car on a closed-circuit track the next morning. The study was conducted in 31 patients with primary insomnia as defined by DSM-IV([R] 1). This study was designed to scientifically and objectively measure a series of parameters that are sensitive to the residual effects of a drug on next-day performance, including information processing, divided attention, psychomotor tasks, working memory, and on-the-road driving.

In this study, there was no statistically significant difference in the primary endpoint of on-the-road BRT, following nighttime administration of LUNESTA 3 mg, compared with placebo. Consistent with the BRT findings, there were no statistically significant differences between subjects who were administered LUNESTA 3 mg versus placebo on a panel of secondary objective and subjective measures of cognitive and psychomotor function. Objective cognitive assessments included: Critical Flicker Fusion (measures central nervous system arousal via information-processing capacity and the ability to discriminate bits of sensory information), Sternberg Short-Term Memory Scanning Task (assesses working memory), and Rapid Visual Information Processing (assesses the performance of attention mechanisms in remaining vigilant to periodically recurring events). Psychomotor function measures included Choice Reaction Time (measures psychomotor performance by assessing the ability to attend to a critical stimulus), Continuous Tracking Task (bilateral task of psychomotor function and divided attention), and Digit Symbol Substitution Test (DSST; psychomotor function test). Subjective assessments of next-day ratings of morning sedation, coordination and mood as assessed by Leeds Sleep Analogue Rating Scale were also not significantly different between treatment groups.

You should not engage in any activity after taking LUNESTA that requires complete alertness, such as driving a car or operating machinery. You should use extreme care when engaging in these activities the morning after taking LUNESTA.

Subjective and objective polysomnography (PSG) assessments of various sleep parameters were also obtained during the study. Patients administered LUNESTA reported significantly improved (p < 0.0001) ease of getting to sleep and sleep quality, and there was no perceived behavior impairment after awakening. Objective measures of sleep by PSG demonstrated significant increases in total sleep time (p=0.0005) and sleep efficiency (p=0.0005); and significant reductions in time awake (p=0.0037), wake time after sleep onset (p=0.005), sleep onset latency (p=0.0001) and latency to persistent sleep (p < 0.0001) for patients administered LUNESTA versus patients administered placebo.

An estimated 36 percent of adult Americans reported suffering from either chronic or occasional insomnia in the last year2. Symptoms of insomnia include difficulty falling asleep, awakening frequently during the night, waking up too early, an inability to fall back to sleep, or awakening feeling unrefreshed.

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 patient age, history and insomnia symptoms. LUNESTA is a Schedule IV controlled substance.

Important Safety Information

LUNESTA is indicated for the treatment of insomnia. 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. 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.

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 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. Sepracor's corporate headquarters are located in Marlborough, Massachusetts.

Forward-Looking Statement 

This news release contains forward-looking statements that involve risks and uncertainties, including statements with respect to the safety, efficacy and potential benefits of LUNESTA brand eszopiclone. Among the factors that could cause actual results to differ materially from those indicated by such forward-looking statements are: Sepracor's ability to fund, and the results of, further clinical trials; the timing and success of submission, acceptance, and approval of additional regulatory filings; the scope of Sepracor's patents and the patents of others; the commercial success of LUNESTA; any changes in the use and/or label of LUNESTA; the ability of the company to attract and retain qualified personnel; and certain other factors that are detailed in the company's quarterly report on Form 10-Q for the quarter ended September 30, 2006 filed with the Securities and Exchange Commission.

In addition, the statements in this press release represent Sepracor's expectations and beliefs as of the date of this press release. Sepracor anticipates that subsequent events and developments may cause these expectations and beliefs to change. However, while Sepracor may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Sepracor's expectations or beliefs as of any date subsequent to the date of this press release.

1Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition

2 Ancoli-Israel et al. SLEEP. 1999;22 (suppl 2):S347-S353

LUNESTA is a registered trademark of Sepracor Inc. DSM-IV is a registered trademark of the American Psychiatric Association.

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