Efficacy of Lemborexant in Adults ≥ 65 Years of Age with Insomnia Disorder

Background: Pharmacologic treatments are available to treat insomnia, a common and burdensome sleep disorder, but may be contraindicated in older adults who are prone to side effects from sleep-promoting drugs. These analyses of sleep diary data from Study E2006-G000-303 (Study 303) investigated the benefits of lemborexant 5 mg (LEM5) and 10 mg (LEM10) in the subgroup age ≥ 65 years with insomnia.

Method: Study 303, a 12-month, double-blind study of LEM5 and LEM10 in adults (age ≥ 18 years) with insomnia disorder (sleep onset and/or maintenance difficulties) assessed subject-reported (subjective) sleep-onset latency (sSOL), sleep efficiency (sSE), wake after sleep onset (sWASO), and total sleep time (sTST). Morning sleepiness/alertness, insomnia severity (Insomnia Severity Index [ISI]), fatigue (Fatigue Severity Scale [FSS]), perceptions of sleep-related medication effects (Patient Global Impression-Insomnia [PGI-I] questionnaire), and safety were also evaluated.

Results: In this subgroup of older adults (≥ 65 years; n = 262), there were significantly larger changes from baseline for sSOL, sSE, sTST, and sWASO with LEM5 and LEM10 versus placebo through month 6 (except sWASO month 1), indicating improvement; these improvements were sustained through month 12. Subject-reported increases in morning alertness were significantly greater with one or both LEM doses versus placebo through month 6 and sustained through month 12. There were significantly larger ISI total and daytime functioning score decreases (improvement) from baseline with LEM versus placebo at months 1, 3, and 6 (total score: both doses; daytime functioning: LEM5 month 1 and both doses months 3 and 6) and decreases from baseline FSS at months 1 and 3 (LEM5) and month 6 (both doses), sustained to month 12. Compared with placebo, more subjects reported that LEM (both doses) positively impacted ability to sleep, time to fall asleep, and TST through month 6, sustained to month 12, with no rebound after drug withdrawal. LEM was well tolerated to month 12; mild somnolence was the most common treatment-emergent adverse event.

Conclusions: Improvements in subject-reported efficacy in LEM-treated adults age ≥ 65 years with insomnia were observed as early as the first week of treatment and sustained through end of month 12. LEM was well tolerated.

Clinical Trials Registration: ClinicalTrials.gov identifier NCT02952820: E2006-G000-303; Study 303; SUNRISE-2 (First posted: October 2016); EudraCT 2015-001463-39 (First posted: November 2016).