Decision Resources, a research and advisory firm focusing on pharmaceutical and health care issues, finds that a drug's effect on latency to sleep onset is the attribute that most influences the prescribing decisions of surveyed primary care physicians (PCPs) in the treatment of insomnia. Clinical data and expert opinion shows that current and emerging therapies offer few advantages in this attribute over the market sales leader, Sanofi-Aventis's Ambien.

The new report, entitled “Insomnia: To Gain Share, Emerging Therapies Must Improve Side Effects Without Compromising Efficacy,” finds that a hypnotic that is free of next-day residual effects would earn a 40% patient share in insomnia, according to the survey of PCPs. The report also finds that although the clinical gold standard in 2006 for insomnia was controlled-release Ambien, Somaxon's Silenor will become the clinical gold standard treatment for insomnia in 2011, following its anticipated approval for the indication in 2009.

Silenor will earn gold standard status owing to its competitive advantages in efficacy and safety over controlled-release Ambien as interviewed sleep experts anticipate that—based on currently available data released by Somaxon—Silenor will feature improvements over Ambien in the measurement of time awake after sleep onset.

"Additional advantages in safety and tolerability over controlled-release Ambien combine to earn Silenor gold-standard status in 2011," said Natalie Taylor, PhD, analyst at Decision Resources. "Interviewed experts expect that Silenor will be perceived by physicians as safer than currently available hypnotics, given the use of the agent's active ingredient at higher doses as an antidepressant for more than 30 years."