Sepracor Inc. has announced preliminary results from its Phase IIIB/IV, 410-patient, four-week, randomized, double-blind, placebo-controlled study evaluating the safety and efficacy of Lunesta brand eszopiclone for the treatment of insomnia in perimenopausal and menopausal women.

In this study, nightly use of Lunesta 3 mg resulted in statistically significant improvement compared with placebo in patient-reported measures of sleep latency (onset of sleep), wake time after sleep onset (WASO; a sleep maintenance measurement of the amount of time spent awake after initially falling asleep), and total sleep time for each week of the four-week study. Lunesta was well tolerated over the treatment period.

"More than 1.3 million women become menopausal each year in the US, adding to the existing 40 million American women of menopausal age who are already going through various neuroendocrine and somatic changes. Those changes may frequently be accompanied by symptoms of insomnia such as waking up during the night and difficulty falling back to sleep, particularly in the presence of hot flashes," said Claudio N. Soares, Associate Professor, Department of Psychiatry and Behavioural Neurosciences, McMaster University.

According to the Agency for Healthcare Research and Quality, up to 40 to 60 percent of perimenopausal, menopausal, and postmenopausal women experience sleep disturbances.

Lunesta is a new non-benzodiazepine indicated for the treatment of insomnia in patients who experience difficulty falling asleep as well as for the treatment of patients who have difficulty sleeping through the night (sleep maintenance difficulty).

The US market for prescription sleep products was approximately $2.1 billion in 2004, excluding products not indicated for the treatment of insomnia that are nonetheless used in its treatment. This represents nearly a 19 per cent increase over the previous year, according to IMS Health information.