Insomnia drug Dayvigo approved in Korea

A DORA-class therapy that targets orexin receptors… improves both sleep onset and sleep maintenance

Confirms reduction in nighttime awakenings versus zolpidem… benefits maintained for six months

Eisai Korea announced on the 24th that its insomnia treatment Dayvigo (lemborexant) received approval from the Ministry of Food and Drug Safety (MFDS) on June 23 for the treatment of adult patients aged 18 years and older who have difficulty initiating or maintaining sleep.

Dayvigo is a dual orexin receptor antagonist (DORA) class drug that works by reversibly binding to orexin receptors OX1R and OX2R, thereby suppressing excessive wakefulness signals mediated by orexin, a neurotransmitter involved in maintaining wakefulness.

Unlike conventional benzodiazepine or non-benzodiazepine (GABA class) sleep medications, which broadly suppress neural activity throughout the brain, Dayvigo promotes sleep by regulating wakefulness, allowing for a more natural sleep process.

The recommended dose is 5 mg taken once daily immediately before bedtime. Depending on patient response and tolerability, the dose may be increased to a maximum of 10 mg.

The approval was based on the global Phase III SUNRISE 1 and SUNRISE 2 studies.

SUNRISE 1 enrolled 1,006 insomnia patients aged 55 years and older and compared Dayvigo with extended-release zolpidem and placebo.

After one month of treatment, latency to persistent sleep (LPS) decreased by 19.5 minutes and 21.5 minutes in the Dayvigo 5 mg and 10 mg groups, respectively, compared with reductions of 7.9 minutes in the placebo group and 7.5 minutes in the extended-release zolpidem group.

Sleep efficiency (SE) increased by 12.9% and 14.1%, respectively, while wake after sleep onset (WASO) decreased by 43.9 minutes and 46.4 minutes.

In particular, wake after sleep onset during the second half of the night (WASO2H) decreased by 27.2 minutes and 28.8 minutes in the Dayvigo 5 mg and 10 mg groups, respectively, compared with a reduction of 21.4 minutes in the extended-release zolpidem group.

Improvements were also confirmed in the SUNRISE 2 study, which evaluated Dayvigo’s long-term efficacy.

In the study, which enrolled 949 adult insomnia patients aged 18 years and older, subjective sleep onset latency (sSOL) at 6 months decreased by 21.8 minutes and 28.2 minutes in the Dayvigo 5 mg and 10 mg groups, respectively, compared with an 11.4-minute reduction in the placebo group.

Subjective sleep efficiency (sSE) increased by 14.2% and 14.3%, while subjective wake after sleep onset (sWASO) decreased by 46.8 minutes and 42.0 minutes, respectively. Response rates for both sleep initiation and sleep maintenance were higher than those observed with placebo, and the benefits were observed and maintained from the first week of treatment through 6 months.

In terms of safety, somnolence was the most frequently reported adverse event in both studies. However, the incidence of serious adverse events was low. No rebound insomnia or withdrawal symptoms were observed, and no new safety concerns emerged during 6 months of long-term treatment.

Hong-byung Koh, CEO of Eisai Korea, said, “Despite the significant impact insomnia has on patients’ daily lives and quality of life, unmet needs remain in treatment. We hope that the approval of Dayvigo will expand patient access to a new treatment option capable of addressing not only sleep onset insomnia but also sleep maintenance insomnia.”