Somaxon Pharmaceuticals, Inc.'s SILENOR Demonstrates Positive Results In Long-Term Phase 3 Clinical Trial In Elderly Patients With Insomnia

SAN DIEGO--Somaxon Pharmaceuticals, Inc. today announced positive results from the company's Phase 3 clinical trial evaluating SILENOR(TM) (doxepin HCl) in elderly patients with chronic primary insomnia. SILENOR(TM) demonstrated a statistically significant improvement compared to placebo in the primary endpoint of this trial, Wake After Sleep Onset (WASO) as measured at night one, for both doses studied (1mg: p=0.0053, 3mg: p less than 0.0001). Statistical significance for this endpoint was also achieved at the end of the twelve week treatment period for both doses studied (1mg: p=0.0330, 3mg: p less than 0.0001).

With the conclusion of this clinical trial, Somaxon has completed six well-controlled clinical trials with SILENOR(TM) for the treatment of insomnia, including four Phase 3 clinical trials. In each of these clinical trials, SILENOR(TM) demonstrated statistically significant results in the trial's designated primary endpoint. These endpoints included measures of both sleep maintenance and sleep onset. The company anticipates filing an NDA with the U.S. Food and Drug Administration (FDA) in the third quarter of 2007, assuming that the company's preclinical studies for SILENOR(TM) are successful and proceed as currently scheduled.

This Phase 3 clinical trial was a randomized, double-blind, placebo-controlled, multi-center, parallel group trial designed to assess the efficacy and safety of 1mg and 3mg of SILENOR(TM) in elderly patients with chronic primary insomnia. The trial enrolled 240 elderly subjects, and efficacy assessments evaluated both objective polysomnography (PSG) and subjective measures of sleep. Subjective efficacy assessments were made both in the sleep laboratory and on an outpatient basis. Safety and efficacy were evaluated over a twelve week period, which we believe represents the longest clinical trial reported to date for insomnia that evaluated efficacy in both the sleep laboratory and outpatient settings.

Silenor is doxepin, a common drug used for treating depression and anxiety disorders. It has heavy sedative effects at concentrations used for depression ( 75-300mg). This is a very low dose 1-3mg, just to reap the sedative effects. It is known as a tricyclic, based on it's 3 ring nucleus structure. Its pharmacological effects include serotonin uptake inhibition, weight gain and sexual dysfunction.

NASDAQ:SOMX is trading up 50 cents in afternoon trading.