Release Details

Treatment With Indiplon Immediate Release Results in Rapid Return to Sleep and Improved Sleep Quality With More Next Day Alertness as Compared to Placebo

SAN DIEGO, Dec. 9 /PRNewswire-FirstCall/ -- Neurocrine Biosciences, Inc. (Nasdaq: NBIX) today announced positive preliminary results from the Company's Phase II/III clinical trial for the immediate release formulation of indiplon, achieving highly statistically significant results in patients with chronic insomnia characterized by waking up in the middle of the night (MOTN). Results show that patients who woke up in the middle of the night and had difficulty in falling back to sleep, and took indiplon, were able to return to sleep rapidly with fewer awakenings and a better quality of sleep. Additionally, there was no evidence of next morning residual effects and patients taking indiplon demonstrated more next day alertness than those who took placebo. This trial marks the first successful MOTN efficacy and safety study that has been conducted with any sedative hypnotic agent.

"People with chronic insomnia frequently wake up in the middle of the night, have difficulty falling back to sleep and experience prolonged middle of the night awakenings. They are often reluctant to take a medication to get back to sleep due to concerns about next day hangover," said Dr. James Walsh, Executive Director, Sleep Medicine and Research Center St. Luke's Hospital, St. Louis, Missouri. "Current medications are designed to help those patients who cannot fall asleep in the beginning of the night, leaving few options for those who wake up in the middle of the night."

The results of this study show that administration of indiplon immediate release 10 mg and 20 mg following MOTN awakening, resulted in a highly statistically significant improvement in the primary endpoint of patient reported Latency to Sleep Onset (LSO) relative to placebo (p<0.003 for 10 mg and p<0.0001 for 20 mg). This improvement was sustained throughout the four-week study with similar results observed in week 1 through week 4. Data also showed that patients treated with indiplon were more alert the next morning upon awakening as compared to placebo using the standard patient self-assessment test of Visual Analog Scale for Sleepiness (VAS). The incidence of adverse events (AEs) for the indiplon treatment groups was similar to what had been previously reported for studies of similar duration and there were no unexpected findings.

All secondary endpoints evaluating indiplon administration following MOTN awakenings were also highly statistically significant for both doses based on patient self assessments, including wake after sleep onset (WASO), number of awakenings after sleep onset (NAASO), total sleep time (TST), and sleep quality and were not associated with any next day residual sedation.

"Indiplon was developed in two formulations, the immediate release and the modified release, to address multiple unmet sleep needs. We are delighted with these clinical results confirming indiplon immediate release as the first insomnia treatment to demonstrate efficacy, safety and lack of next morning residual effects when treating patients who wake up in the middle of the night and have difficulty falling back to sleep," said Dr. Henry Pan, Executive Vice President and Chief Medical Officer for Neurocrine Biosciences. "With this new set of data, we believe that the two formulations of indiplon will fill the multiple unmet needs experienced by patients with sleep disorders."

Study Design

The study was a Phase II/III randomized, placebo-controlled, double-blind, parallel-group, multi-center study to assess the efficacy and safety of MOTN administration of indiplon immediate release 10 mg and 20 mg doses as compared to placebo in 264 adult patients with chronic primary insomnia with a history of frequent and prolonged MOTN awakenings. This study was conducted on an outpatient basis over a four-week treatment period. The primary endpoint for this study was patient reported Latency to Sleep Onset (LSO). Patients administered indiplon or placebo upon MOTN awakening and were required to remain in bed for at least four hours post dosing. Next day assessment of residual effects as measured by the Visual Analog Scale of Sleepiness was recorded by the patient upon awakening in a diary.

About Indiplon

Indiplon is a unique non-benzodiazapine agent that acts on a specific site of the GABA-A receptor. Indiplon has been shown to bind preferentially to the specific subtype of GABA-A receptors within the brain believed to be responsible for promoting sleep. There are two formulations of indiplon, immediate release and modified release are being studied in clinical trials to address different types of sleep problems

About Neurocrine Biosciences

Neurocrine is conducting one of the most comprehensive clinical programs in insomnia to address the multiple needs of younger and older adult patients with insomnia such as sleep initiation, sleep maintenance, and long-term administration. Neurocrine has initiated and is completing all of its Phase III safety and efficacy trials to support a New Drug Application (NDA) expected in the first half of 2004 for indiplon for multiple insomnia indications. The Phase III program alone will have data from approximately 5,000 patients with different types of insomnia.

Insomnia is a prevalent condition in the United States, with more than one-half of the adult population reporting trouble sleeping a few nights per week or more, according to the National Sleep Foundation's (NSF) Sleep in America Poll 2002. Approximately 35 percent of the adult population reports that they have experienced insomnia every night or almost every night within the past year. Insomnia remains a disorder with high unmet medical needs, including prolonged awakenings during the night with difficulty falling back to sleep.

Neurocrine Biosciences, Inc. is a product-based biopharmaceutical company focused on neurological and endocrine diseases and disorders. Our product candidates address some of the largest pharmaceutical markets in the world including insomnia, certain female and male disorders, anxiety, depression, diabetes, multiple sclerosis, irritable bowel syndrome, eating disorders, pain, and autoimmunity. Neurocrine Biosciences, Inc. news releases are available through the Company's website via the Internet at http://www.neurocrine.com.

In addition to historical facts, this press release may contain forward-looking statements that involve a number of risks and uncertainties. Among the factors that could cause actual results to differ materially from those indicated in the forward looking statements are risks and uncertainties associated with the Company's indiplon clinical development program and planned regulatory activities. Specifically, the risks and uncertainties the Company faces with respect to its indiplon program include, but are not limited to, risk that indiplon may not successfully proceed through Phase III clinical trials or Phase III clinical trials may fail to demonstrate that indiplon is safe and effective in treating humans; risk that the Company may not complete indiplon Phase III clinical trials on the Company's projected timelines for various reasons, including the possibility that patient recruitment may be slower than expected; risk that the clinical investigators and contract research organizations upon which the Company relies to conduct its clinical programs may not be diligent, careful or timely, and may make mistakes, in the conduct of the programs; risk relating to the Company's dependence on contract manufacturers for clinical drug supply and compliance with regulatory requirements for marketing approval; risk that the Company may not successfully co-ordinate the completion and submission of planned regulatory filings on the Company's projected timelines; risk that the Company may not receive regulatory approval for indiplon or approval may be delayed; risks associated with the Company's dependence on corporate collaborators for commercial manufacturing and marketing and sales activities; uncertainties relating to patent protection and intellectual property rights of third parties; risks and uncertainties relating to competitive products and technological changes that may limit demand for the Company's products; risk that the Company will be unable to raise additional funding required to complete development of all of its product candidates; and the other risks described in the Company's Form 10-K for the year ended December 31, 2002, the Company's most recent report on Form 10-Q and the Company's final prospectus supplement and accompanying prospectus relating to its recent offering. Neurocrine undertakes no obligation to update the statements contained in this press release after the date hereof.

SOURCE Neurocrine Biosciences, Inc.