Release Details

Indiplon Modified Release Shows Statistically Significant Improvement In Sleep Maintenance and Sleep Quality

SAN DIEGO, Sept. 24 /PRNewswire-FirstCall/ -- Neurocrine Biosciences, Inc. (Nasdaq: NBIX) today announced preliminary top line results from the Company's first indiplon modified release Phase III clinical trial, achieving statistically significant results that demonstrate patients with chronic insomnia taking indiplon 30 mg fell asleep more rapidly and stayed asleep longer. The data released today support the objective results demonstrated with indiplon utilizing polysomnographic analyses of patients in previous clinical trials.

The modified release formulation of indiplon following nightly administration of 30 mg over a two week period demonstrated a statistically significant improvement in the primary endpoint of patient reported Total Sleep Time (sTST) relative to placebo at both week 1 (placebo 332.5 min, indiplon 376.1 min, p<0.0001) and week 2 (placebo 342.3 min, indiplon 370.0 min, p<0.004). These data confirm that patients on indiplon slept significantly longer than those taking placebo and that the effect was sustained over the two week treatment period.

Indiplon modified release also demonstrated statistically significant efficacy results in sleep maintenance as compared to placebo on multiple secondary endpoints. These endpoints included patient reported Wake After Sleep Onset (sWASO, p<0.0003 Week 1 and p<0.02 Week 2), Total Wake Time (sTWT, p<0.0001 Week 1 and 2), and Number of Awakenings after Sleep Onset (sNAASO, p<0.0001 Week 1 and 2) in favor of indiplon compared to placebo.

In addition a key secondary efficacy endpoint of patient reported Latency to Sleep Onset (LSO), or the amount of time it took subjects to fall asleep, also demonstrated statistically significant improvements in the indiplon treated group as compared to the placebo group (p<0.02 at week 1 and p<0.04 at week 2).

Evaluation of treatment response was also assessed by both patients and investigators. Indiplon patients reported a statistically significant improvement in the quality of their sleep compared to the placebo group (p<0.0001). Patient reported Global Impression (PGI) assessed for overall effect of sleep, time to sleep, amount of sleep, sleep quality, and strength of medication, also showed significant improvement over placebo (p<0.002). Investigator reported Global Rating for Severity of insomnia and Change as a result of treatment were both in favor of indiplon (p<0.0001).

"The study results reinforce the potential of indiplon modified release in treating Sleep Maintenance Insomnia and in improving Sleep Quality in patients with chronic insomnia problems," said Dr. Thomas Roth, Chief, Division Head, Sleep Disorders and Research Center, Henry Ford Hospital. "The data released to date for both the immediate and modified release formulations of indiplon have demonstrated the efficacy of the compound to address the many different needs of the insomnia patient population based on several sleep parameters."

Safety results demonstrated that the 30 mg dose of the modified release formulation of indiplon was well tolerated. There were no serious adverse events in the study. The adverse events reported in the study were in line with the pharmacological effect of indiplon and were consistent with previous clinical trial results.

"These results demonstrate that indiplon modified release is highly effective in patients with sleep maintenance insomnia showing positive outcomes in all primary and secondary endpoints. In addition to this being the first Phase III outpatient study, we are also reporting for the first time investigator and patient reported global ratings of the effectiveness of indiplon in this patient population," said Henry Pan, Executive Vice President and Chief Medical Officer for Neurocrine Biosciences.

Study Design and Overall Indiplon Program

The study was a randomized, double-blind, placebo-controlled, parallel group, multicenter Phase III clinical trial designed to assess the safety and efficacy of the modified release formulation of indiplon tablets (30 mg). The study involved 211 adult patients at 32 centers in the U.S. with Chronic Primary Insomnia. Patients received treatment on an outpatient basis over a two-week treatment period.

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 over 4,000 patients with different types of insomnia.

Insomnia is a prevalent neurological disorder 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% of the adult population reports that they have experienced insomnia every night or almost every night within the past year. Despite this widespread prevalence, insomnia remains a disorder with high unmet medical needs, including the ability to maintain sleep throughout the night without next-day residual effects.

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 more selectively than the currently marketed non-benzodiazepines at the specific subtype of GABA-A receptors within the brain believed to be responsible for promoting sleep.

About Neurocrine Biosciences

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 Phase III 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.