Lemborexant in Delayed Sleep Phase Syndrome

Phase 4

Recruiting

• Conditions: Delayed Sleep Phase Syndrome
• Interventions: Drug: Placebo; Drug: Lemborexant

• Registration Number: NCT06874855
• Lead Sponsor: University of California, San Francisco

Brief Summary

The purpose of the study is to evaluate whether Lemborexant is more effective than placebo in shortening sleep onset latency in patients with delayed sleep phase syndrome (both type 1 and type 2). This will be tracked using sleep logs as well as actigraphy.

In this 2-year study, the investigators will examine if Lemborexant administered 5-10 mg nightly taken at desired bedtime (at least 2 hours prior to self-reported sleep onset habitual time) can improve the symptoms of Delayed Sleep Phase Syndrome.

Detailed Description

Delayed sleep phase syndrome (DSPS) is a disorder in which a person's sleep is delayed by two hours or more beyond what is considered an acceptable or conventional bedtime. The delayed sleep then causes difficulty in being able to wake up at the desired time. In DSPS, bedtime is shifted later than the general population such that individuals have difficulty getting enough sleep to meet their sleep need before they have to get up for their daytime obligations (work, school, childcare, etc.). As a result, patients experience daytime impairment including daytime sleepiness and cognitive impairment. DSPS, if maintained in adulthood is associated with numerous deleterious health effects, although causality is not well established. The prevalence of this condition is approximately 7-16% among adolescents and young adults.

Study Timeline

• Study Start: 2023-03-13
• Study First Submitted: 2025-03-07
• Study First Submitted QC: 2025-03-07
• Study First Posted: 2025-03-13
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-22
• Last Update Posted: 2025-04-24
• Primary Completion: 2027-05-31
• Study Completion: 2027-05-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• Participants will be required to be 18 years of age or older and have delayed sleep phase syndrome (DSPS). Questionnaires will be used to identify potential confounders and to confirm a potential diagnosis of DSPS based on ICSD3 criteria: a) Sleep is delayed by two hours or more beyond what is considered an acceptable or conventional bedtime for the subject (their desired bedtime). b) Subjects not able to fall asleep if trying to sleep before the later bedtime; c) This is interfering with their wishes/having a social impact. Concomitant medications will be allowed, though dosages will be required to remain fixed throughout participation in the study. The participant also needs to be willing and able to comply with all aspects of the protocol.

Exclusion Criteria

• Clinically significant depression (PHQ-9 score of 10 or more), anxiety disorder (GAD- 7 score of 10 or more), substance use disorder, any other sleep disorder, or any medical disorder/therapy that could interfere with the trial
• Use of medications with significant effects on sleep-wake function (insomnia therapies, stimulants)- unless they are discontinued at least 5 half-lives prior to study participation. Non-sedative antidepressants or SSRI will be allowed if at a stable dose in the absence of concomitant severe depression or severe anxiety.
• Use of CYP3A inhibitors and CYP3A inducers, at least 1 week (or five half-lives, whichever is longer) prior to the first day of the baseline phase.
• Pregnancy (verified by urine pregnancy test on visits 1, 2, and 3) or plan to become pregnant in the next 3 months or currently breastfeeding.
• Shift workers or subjects working unusual hours.
• Transmeridian travel across more than 3 time zones 4 weeks prior to the screening phase.
• Transmeridian travel across more than 2 time zones during this trial (including the screening phase).
• Having a positive drug test or being unwilling to refrain from using illegal drugs or marijuana during this trial.
• Any clinically abnormal symptom or organ impairment found by medical history at Screening or Baseline and physical examinations, vital signs, or laboratory test results that require medical treatment.
• Impaired liver function (values for enzymes aspartate transaminase (AST) and alanine transaminase (ALT) > 1.5 times the Upper Limit of Normal).
• Known to be human immunodeficiency virus positive.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Patients receive placebo to match Lemborexant for 14 days
Lemborexant	Lemborexant	Patients receive Lemborexant 5mg for 7 days and may be dose adjusted to 10mg. Patients continue to take Lemborexant 5mg or 10mg for an additional 7 days

Primary Outcome Measures

Name	Time	Method
Change in actigraphy sleep latency onset	From 2 weeks prior to randomization to 4 weeks post randomization	Sleep latency is the time from laying down until falling asleep. Actigraphy data obtained using Axivity- AX6.

Secondary Outcome Measures

Name	Time	Method
Change in Epworth Sleepiness Scale (ESS)	From randomization to 4 weeks post randomization	This is a scale to evaluate daytime sleepiness. Range from 0 to 24 points (higher scores mean more sleepiness).
Change in Karolinska Sleepiness Scale (KSS)	From randomization to 4 weeks post randomization	Self-report for daytime sleepiness with 1 being extremely alert and 10 being extremely sleepy, can't keep awake.
Change in sleep diary derived sleep onset latency	From 2 weeks prior to randomization to 4 weeks post randomization	Sleep latency is the time from laying down until falling asleep as estimated by patient in dairy.
Sleep Regularity Index	From 2 weeks prior to randomization to 4 weeks post randomization	Sleep Regularity Index is defined as the percentage probability of a person being asleep (or awake) at any two time points 24 hours apart. Actigraphy data obtained using Axivity- AX6.
Change in actigraphy derived total sleep time	From 2 weeks prior to randomization to 4 weeks post randomization	Actigraphy data obtained using Axivity- AX6.
Change in sleep diary derived total sleep time.	From 2 weeks prior to randomization to 4 weeks post randomization	Estimated by patient in dairy.
Change in mean actigraphy derived wake time	From 2 weeks prior to randomization to 4 weeks post randomization	Wake time is total time awake over night after sleep onset. Actigraphy data obtained using Axivity- AX6.
Change in mean sleep diary derived wake time	From 2 weeks prior to randomization to 4 weeks post randomization	Wake time is total time awake over night after sleep onset as estimated by patient in dairy.

Trial Locations

Locations (1)

University of California San Francisco; 🇺🇸 San Francisco, California, United States