The effects of lemborexant on insomnia-related fatigue: a plain language summary

What is this summary about? This is a summary of an article originally published in the journal Postgraduate Medicine. Lemborexant is a type of medication called a dual orexin receptor antagonist (often abbreviated to DORA) that is approved for treating people with insomnia, a sleep disorder in which people have trouble falling asleep, staying asleep or both. Two studies, one called SUNRISE-1 (Study 304), which lasted one month, and SUNRISE-2 (Study 303), which lasted 12 months, looked at the effects of lemborexant on sleep compared to placebo in people with insomnia. People with insomnia often experience fatigue (or tiredness) during the daytime, which affects their daily lives and health, and often have other conditions which can also cause fatigue. This summary reports an analysis that looked at whether lemborexant improves fatigue during the daytime as well as nighttime symptoms of insomnia in all participants and in participants with clinically significant fatigue before treatment. What were the results? In both studies, participants completed a questionnaire, called the Fatigue Severity Scale, that measured how significant their fatigue was. The researchers looked at the change in fatigue over time in participants treated with lemborexant compared with those given placebo. They also looked at the change in a group of participants who reported clinically important levels of fatigue at the beginning of the study. People in these studies also completed diaries about how long it took them to fall asleep and how long they slept. The researchers compared improvements in fatigue with changes in how participants slept over time. Overall, lemborexant reduced daytime fatigue compared with placebo in all study participants. It also reduced daytime fatigue in the smaller group of participants who had clinically significant fatigue at the beginning of the study. The reductions in fatigue seen with lemborexant remained during 1 year of treatment. There was also a relationship between reduced fatigue, falling asleep faster and not waking up as much. What do the results mean? Researchers concluded that in addition to improving sleep in people with insomnia, lemborexant can reduce daytime fatigue.