Background: Individuals with moderate to severe chronic obstructive pulmonary disease (COPD) have poor sleep quality. This study evaluated the effects of ramelteon, an MT(1)/MT(2) melatonin receptor agonist indicated for insomnia treatment on respiration in this population.
Materials and methods: This double-blind, crossover study enrolled 25 subjects (>or=40 years) with moderate to severe COPD (FEV(1)/FVC <70% and FEV(1) between 50 and 80% of predicted value [moderate], or FEV(1)/FVC <70% and FEV(1) <50% of predicted value [severe]). Subjects received ramelteon 8 mg or placebo for one night 30 min before polysomnographic monitoring, including measurement of oxygen saturation (SaO(2)) and respiratory effort and flow. Subjects crossed to alternate treatment after a 5- to 10-day washout. The primary endpoint was mean SaO(2) for the entire night.
Results: No significant difference in SaO(2) for the entire night was observed with ramelteon vs placebo (92.2% vs 92.5%, P = 0.576). Mean SaO(2) was similar between ramelteon and placebo for each hour of the night, each sleep stage, the number of minutes that SaO(2) was <80% and <90%, and mean apnea-hypopnea index. There was a significant difference in total sleep time (389.0 vs 348.4 min, P = 0.019) and sleep efficiency (81.0 vs 72.6%, P = 0.019), and latency to persistent sleep was shorter (23.1 vs 56.9 min, P = 0.051), with ramelteon vs placebo. All adverse events were mild to moderate; none led to study discontinuation.
Conclusion: Ramelteon did not produce respiratory depressant effects as measured by oxygenation or abnormal breathing events in subjects with moderate to severe COPD. Ramelteon was well tolerated in this population.