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Insomnia Drug Effective in Patients With Comorbid Alzheimer’s

May 13, 2019

Insomnia drug suvorexant (Belsomra C-IV) added nearly a half hour more sleep per night than did placebo in people with mild-to-moderate Alzheimer’s disease dementia and insomnia, according to results presented at the 2019 American Academy of Neurology Annual Meeting in Philadelphia, Pennsylvania.

The phase 3, double-blind trial randomized participants to 4 weeks of treatment with Merck’s suvorexant 10 mg (which, based on response, could be increased to 20 mg) or placebo. All participants had mild-to-moderate Alzheimer’s disease dementia (determined by a score of 12-26 on the Mini Mental State Examination) and insomnia, with a mean total sleep time of less than 6 hours. Over the course of the study, 77% of patients who received suvorexant increased their dose to 20 mg after 2 weeks.

Among 136 participants who received suvorexant, total sleep time as measured by overnight polysomnography increased an average 73.4 minutes, according to the study, compared with an average gain of 45.2 minutes for the 141 participants who received placebo. Meanwhile, minutes awake after sleep onset decreased an average 41.8 minutes with suvorexant compared with an average 32.5-minute decrease with placebo.

The Complex Relationship Between Insomnia and Mood Disorders

The most common adverse event was mild-to-moderate drowsiness, which was reported for 4.2% of participants who received suvorexant and 1.4% of participants who received placebo. Other adverse events included headache, dry mouth, and falls.

“Insomnia and other sleep disturbances are more common in people with Alzheimer’s disease dementia, but evidence for the efficacy and safety of sleep medications in this population remains limited,” said W. Joseph Herring, MD, PhD, associate vice president, Global Clinical Research, Neuroscience, Merck Research Laboratories.

“We are encouraged by the efficacy and safety results of Belsomra in those living with Alzheimer’s disease dementia. Merck plans to file these data with the US Food and Drug Administration for potential inclusion into the Belsomra prescribing information.”

—Jolynn Tumolo


Merck’s Belsomra (suvorexant) C-IV meets primary efficacy endpoint in phase 3 trial for the treatment of insomnia in people with mild-to-moderate Alzheimer’s disease dementia [press release]. Kenilworth, New Jersey: Merck; May 7, 2019.

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