A Phase 1/2 interventional study of Lemborexant 5 MG [Dayvigo] Period 1 and Placebo Period 1 in OSA - Obstructive Sleep Apnea, sponsored by Chulalongkorn University. Not yet recruiting at 1 site in Thailand. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-07-06.
Sponsored by Chulalongkorn University · Phase 1/2, Interventional, and Treatment
The goal of this clinical trial is to investigate the 1-month treatment effects of different dose of lemborexant in moderate OSA adult patients (18-65 years of age) with low arousal threshold.
The main questions it aims to answer are:
Primary outcome measure: Apnea/hypopnea index (AHI)
Secondary outcome measure:
Polysomnography parameters
Actigraphy parameters
Sleep diary parameters (Appendix 5)
Researchers will compare placebo to see if there is a difference in AHI.
Participants will
2,240 studies on the registry are indexed under Sleep Apnea, Obstructive; 475 are open to participants now.
This study's planned enrollment of 36 is below the median of 52 across 1,472 interventional studies indexed under Sleep Apnea, Obstructive.
Browse Sleep Apnea, Obstructive studies →Chulalongkorn University is the lead sponsor of 322 studies on the registry; 66 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Inclusion criteria
Individuals are eligible for participation in this study if they have all of the followings:
Individuals were not eligible for participation in this study if they have any of the followings:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CYP3A (CYP3A4) inhibitors and inducers
CYP3A is a group of enzymes, mainly CYP3A4, in the liver and gut that break down many medicines. Some medicines, supplements and foods (grapefruit, St John’s wort) slow them down or speed them up, which changes how much of a study drug stays in the body.
Studies list them so they can be avoided or switched; bring a list of everything you take, including supplements.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive two treatment sequences. Participants will complete three overnight sleep studies and cross-over with 2-week wash-out period The participants will receive lemborexant 5 mg per day before sleep for a total of 30 days. On the day 30 participants will receive the lemborexant 5 mg 5 minutes before lights-out at the sleep laboratory for overnight polysomnography. After 2 week wash-out period, the participants will cross to the placebo or lemborexant 10 mg arm with same repeat of another 2 phases.
Drug: Lemborexant 5 MG [Dayvigo] Period 1 · Drug: Lemborexant 5 MG [Dayvigo] Period 2 · Drug: Lemborexant 5 MG [Dayvigo] Period 3
Participants will receive two treatment sequences. Participants will complete three overnight sleep studies and cross-over with 2-week wash-out period The participants will receive placebo per day before sleep for a total of 30 days. On the day 30 participants will receive the placebo 5 minutes before lights-out at the sleep laboratory for overnight polysomnography. After 2 week wash-out period, the participants will cross to the lemborexant 5 or 10 mg arm with same repeat of another 2 phases.
Drug: Placebo Period 1 · Drug: Placebo Period 2 · Drug: Placebo Period 3
Participants will receive two treatment sequences. Participants will complete three overnight sleep studies and cross-over with 2-week wash-out period The participants will receive lemborexant 10 mg per day before sleep for a total of 30 days. On the day 30 participants will receive the lemborexant 10 mg 5 minutes before lights-out at the sleep laboratory for overnight polysomnography. After 2 week wash-out period, the participants will cross to the placebo or lemborexant 5 mg arm with same repeat of another 2 phases.
Drug: Lemborexant 10 MG [Dayvigo] Period 1 · Drug: Lemborexant 10 MG [Dayvigo] Period 2 · Drug: Lemborexant 10 MG [Dayvigo] Period 3
Participants will receive lemborexant 5 mg per day for 30 days during first period
Participants will receive placebo 5 mg per day for 30 days during the first period
Participant will receive lemborexant 5 mg per day for 30 days during the second period
Participant will receive placebo 5 mg per day for 30 days during the second period
Participants will receive lemborexant 5 mg per day for 30 days during third period
Participants will receive placebo per day for 30 days during third period
Participants will receive lemborexant 10 mg per day for 30 days during first period
Participants will receive lemborexant 10 mg per day for 30 days during second period
Participants will receive lemborexant 10 mg per day for 30 days during third period
Apnea/hypopnea index (AHI)
Apnea/hypopnea index (AHI) measured by polysomnography (scale: events/hour: minimum 0 event/hour - no maximum scoring; higher scores mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Mean and nadir oxygen saturation
Mean and nadir oxygen saturation measured by polysomnography (scale: percent: minimum 0% - maximum 100%; higher scores mean better outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Sleep efficiency
Sleep efficiency measured by polysomnography (scale: percent: minimum 0% - maximum 100%; higher scores mean better outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Wake after sleep onset (WASO)
Wake after sleep onset (WASO) measured by polysomnography (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Sleep latency
Sleep latency measured by polysomnography (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
REM latency
REM latency measured by polysomnography (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Percentage of time spent in NREM stage 1-3 and REM stage
Percentage of time spent in NREM stage 1-3 and REM stage measured by polysomnography (scale: percent: minimum 0% - maximum 100%; higher scores in NREM stage 3 and REM mean better outcome but higher scores in NREM stage 1 and 2 mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
Arousal index
Arousal index measured by polysomnography (scale: events/hour: minimum 0 event/hour - no maximum scoring; higher scores mean worse outcome)
Time frame: At day 30 during the overnight in-laboratory of each study period
OSLER error index
Oxford Sleep Resistance Test (OSLER) test (scale: events/hour: minimum 0 event/hour - no maximum scoring; higher scores mean worse outcome)
Time frame: On the morning of the in-laboratory polysomnography
Epworth Sleepiness Scale (ESS)
Epworth Sleepiness Scale (ESS) questionnaires (scale: point: minimum 0 point - maximum 24 point; higher scores mean worse outcome)
Time frame: Baseline (prior to intervention) and at day 30 of intervention before the overnight in-laboratory of each study period
Functional Outcome of Sleep Questionnaire-short version (FOSQ-10T)
Functional Outcome of Sleep Questionnaire-short version (FOSQ-10T) (scale: point: minimum 5 point - maximum 20 point; higher scores mean better outcome)
Time frame: Baseline (prior to intervention) and at day 30 of intervention before the overnight in-laboratory of each study period
Pittsburgh Sleep Quality Index
Pittsburgh Sleep Quality Index (scale: point: minimum 0 point - maximum 21 point; higher scores mean worse outcome)
Time frame: Baseline (prior to intervention) and at day 30 of intervention before the overnight in-laboratory of each study period
Total sleep time
Total sleep time measured by actigraphy (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean better outcome)
Time frame: During day 1-29 of intervention
Sleep efficiency
Sleep efficiency measured by actigraphy (scale: percent: minimum 0% - maximum 100%; higher scores mean better outcome)
Time frame: During day 1-29 of intervention
Wake after sleep onset (WASO)
Wake after sleep onset (WASO) measured by actigraphy (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: During day 1-29 of intervention
Sleep latency
Sleep latency measured by actigraphy (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: During day 1-29 of intervention
Total sleep time
Total sleep time recorded by sleep diary (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean better outcome)
Time frame: During day 1-29 of intervention
Sleep efficiency
Sleep efficiency recorded by sleep diary (scale: percent: minimum 0% - maximum 100%; higher scores mean better outcome)
Time frame: During day 1-29 of intervention
Wake after sleep onset (WASO)
Wake after sleep onset (WASO) recorded by sleep diary (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: During day 1-29 of intervention
Sleep latency
Sleep latency recorded by sleep diary (scale: minute: minimum 0 minute - no maximum scoring; higher scores mean worse outcome)
Time frame: During day 1-29 of intervention
Sleep quality
Sleep quality recorded by sleep diary (5-point Likert scale of 1-5; higher score mean better outcome)
Time frame: During day 1-29 of intervention
Plan to share: No
No publications or documents are linked to this record.
Start is estimated for Sep 2026; primary completion for Jun 2028, 21 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Lemborexant