Efficacy and safety of ramelteon in Japanese adults with chronic insomnia: a randomized, double-blind, placebo-controlled study

Expert Rev Neurother. 2011 Feb;11(2):215-24. doi: 10.1586/ern.10.197.


This randomized, double-blind, placebo-controlled study assessed the efficacy and safety of ramelteon 4 and 8 mg in Japanese adults with chronic insomnia. A secondary objective was to evaluate efficacy and safety when doses were uptitrated from placebo, ramelteon 4 and 8 mg to 4, 8 and 16 mg, respectively. Patient-reported sleep data were collected using sleep diaries. There was no statistically significant difference between ramelteon and placebo in the change in subjective sleep latency (sSL) in the full analysis set (n = 1130). Significant improvement was observed in the change in subjective total sleep time with ramelteon 8 mg at week 1. In post hoc analyses, ramelteon 8 mg reduced sSL in individuals with smaller fluctuations (within ±30 min) of sSL at baseline, in those with a shorter (<1 year) history of insomnia and in individuals who had not used benzodiazepines. Ramelteon up to 16 mg nightly was safe and well tolerated.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Humans
  • Hypnotics and Sedatives / adverse effects*
  • Hypnotics and Sedatives / therapeutic use*
  • Indenes / adverse effects*
  • Indenes / therapeutic use*
  • Japan
  • Male
  • Placebos
  • Sleep Initiation and Maintenance Disorders / drug therapy*
  • Time Factors
  • Treatment Outcome


  • Hypnotics and Sedatives
  • Indenes
  • Placebos
  • ramelteon