Delayed Sleep Phase SyndromeNCT06471374
Pathophysiology of Circadian Rhythm Delayed Sleep Wake Phase Disorder
A study testing Circadian rhythm assessment and Light sensitivity assessment in people with Delayed Sleep Phase Syndrome and Delayed Sleep Phase, run by University of Colorado, Boulder at 2 sites in United States.
Trial summary
The goal of this study is to understand factors that contribute to delayed sleep wake phase disorder (DSWPD). The investigators will examine whether patients with DSWPD exhibit alterations in circadian rhythms and sensitivity to light compared to healthy controls. Read more about this study
- Who is it for?
- Ages 16 to 40 yearsHealthy volunteers can take part
- Conditions the study is for
- Delayed Sleep Phase Syndrome, Delayed Sleep Phase
- What is being tested?
- Circadian rhythm assessment and Light sensitivity assessment
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 66 participants
- Where
- 2 sitesUnited States
- Study dates
- 2 Apr 2024to Jul 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 16 to 40 years
- All sexes
- Healthy volunteers accepted
- Child, Adult
Who may be able to join
- Delayed sleep wake phase disorder diagnosis
- Altitude history: currently residing at Denver altitude or higher
- BMI normal to moderately overweight
Who cannot join
- Recent medical condition
- Psychiatric disorder
- Sleep disorder
- Medication use
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
United States2 sites, 2 recruiting
- Recruiting
University of Colorado
Boulder, Colorado, 80303
Kenneth Wright, PhD, 303-735-1923, sleep.study@colorado.edu
- Recruiting
Northwestern University
Chicago, Illinois, 60611
Phyllis Zee, MD, PhD, (312) 695-7950
Phyllis Zee, MD, PhD
About this study
The goal of this study is to understand factors that contribute to delayed sleep wake phase disorder (DSWPD). The investigators will examine whether patients with DSWPD exhibit alterations in circadian rhythms and sensitivity to light compared to healthy controls. The investigators will also test a new method of predicting circadian rhythms form a blood sample.
Read the detailed description
- The research parts of the study are 6.5 weeks long and the study, including screening visits, involves 6 in-person visits to the Boulder campus.
- If participants qualify for the study and choose to participate, there will be two visits where participants will pick up research equipment to wear at home for 1-2 weeks of ambulatory monitoring before being studied in the laboratory. The first ambulatory monitoring session is for 2 weeks and the second is one week.
- On the first ambulatory monitoring session the investigators will have participants answer questions about participant's mood and cognition.
- On both ambulatory monitoring sessions, the investigators will also ask participants to wear a blood sugar monitor and track the timing of when participants eat using a phone app. The investigators will also have participants wear a wrist worn sleep and light monitor plus a daily sleep log and Google form of when participants go to bed and wake up.
- Next will be a visit where participants will spend 66 hours (2.75 days) in the laboratory.
- While living in the lab, participants will not be aware of the time of day (e.g., no clocks, internet, cell phones), and the investigators will schedule participant's activities.
- The investigators will ask participants to remain seated in bed and awake for up to ~39 hours, with the head of the bed raised. Participants will be studied under dim light similar to candlelight.
- The investigators will frequently take saliva samples for more than 24 hours when the investigators will ask participants to stay awake. The investigators will also take four blood samples.
- The investigators will also ask participants to perform reaction time tests, tests of participant's ability to think, and to complete ratings of how participants feel multiple times each day that participants are in the lab.
- The investigators will also record participant's brain wave activity, muscle activity, eye movements, and heart rate when participants stay awake and during ~9h sleep opportunities.
- The investigators will then ask participants to sleep normally at home for ~2 weeks, followed by 1 week of ambulatory monitoring.
- Finally, there will be a visit where participants will spend 48 hours (2 days) in the laboratory.
- While living in the lab, participants will not be aware of the time of day (e.g., no clocks, internet, cell phones) and the investigators will schedule participant's activities.
- The investigators will expose participants to different light levels (dim light similar to candlelight and typical room light).
- The investigators will frequently take saliva samples.
- The investigators will also ask participants to perform reaction time tests, tests of participant's ability to think, and to complete ratings of how participants feel multiple times each day that participants are in the lab.
- The investigators will also record participant's brain wave activity, muscle activity, eye movements, and heart rate when participants are awake and while participants sleep.
- Conditions
- Delayed Sleep Phase Syndrome, Delayed Sleep Phase
- Being tested
- Circadian rhythm assessment, Light sensitivity assessment
- Medical subject headings
- Sleep Disorders, Circadian Rhythm
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Circadian rhythm assessmentBehavioural
Participants will arrive approximately 8 hours before participant's scheduled bedtime to practice ability to think testing and a 9-hour sleep study. Participants will live in the laboratory for approximately 66 hours (2.75 days). Upon awakening in the morning, participants will start a routine of up to 39 hours of wakefulness, under bedrest conditions. Saliva will be sampled frequently and blood will be drawn 3 times. Reaction time, ability to think, and subjective rating tests will be performed frequently. Participants will be provided scheduled bathroom breaks when participants will use a commode next to the bed. Outside these scheduled bathroom breaks, participants will be provided a bedpan to use to go to the bathroom. At the end of the research procedures for Visit 4 participants will be given a recovery sleep opportunity and be discharged from the lab in the morning near participant's typical waketime.
Light sensitivity assessmentBehavioural
Participants will arrive in the afternoon to practice ability to think testing and a 9-hour sleep study. Participants will live in the laboratory for approximately 48 hours (2 days). Upon awakening in the morning, participants will be exposed to dim candlelight and then later in the day alternating intensities of dim and room light when we keep participants awake for up to 23 hours (We will ask participants to remain in bed seated for ~12.5 hours). Saliva will be sampled frequently. Reaction time, ability to think, and subjective rating tests will be performed frequently. Participants will then have a second 9-hour sleep opportunity.
| Study group | Role | What they receive |
|---|---|---|
| Assessment | Experimental | Circadian rhythms and light sensitivity Receives: Behavioral: Circadian rhythm assessment; Behavioral: Light sensitivity assessment |
What is being measured
The primary outcome is the main question the study is designed to answer.
Core body temperature
Body temperature measured with a pill
Measured: Continuously for 1. up to 39 and 2. 23 hours
Glucose
Blood sugar levels
Measured: Continuously for 1. up to 39 and 2. 23 hours
Subjective sleepiness
Self reported sleepiness
Measured: Every 2 hours
Psychomotor vigilance
Attention/Vigilance performance
Measured: Every 2 hours
Secondary outcomes (2)
Skin temperature
skin body temperature
Measured: Continuously for 1. up to 39 and 2. 23 hours
Melatonin
Melatonin levels in saliva
Measured: Hourly for 1. up to 39 hours and 2. every 20 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Jun 2024
- Study start2 Apr 2024
- Primary completionJul 2028 (estimated)
- Study completionJul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Delayed Sleep Phase SyndromeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 66 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Colorado, Boulder
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Kenneth Wright, University of Colorado, Boulder
- Investigators
- Kenneth Wright, PhD, Principal investigator, University of Colorado, Boulder
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06471374
- Sponsor's protocol ID
- 23-0285
- Other IDs
- 1R01HL159647-01
- Status last verified
- Jun 2026
- First submitted
- 18 Jun 2024
- Last updated
- 17 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Pathophysiology of Circadian Rhythm Delayed Sleep Wake Phase Disorder
- ClinicalTrials.gov ID
- NCT06471374
- Acronym / sponsor ID
- 23-0285
- Conditions
- Delayed Sleep Phase Syndrome, Delayed Sleep Phase
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 66 participants (estimated)
- Lead sponsor
- University of Colorado, BoulderUniversity, hospital or other
- Collaborators
- Northwestern University, National Heart, Lung, and Blood Institute (NHLBI)
- Study start
- 2 Apr 2024 (actual)
- Primary completion
- Jul 2028 (estimated)
- Study completion
- Jul 2028 (estimated)
- First posted
- 24 Jun 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this study is to understand factors that contribute to delayed sleep wake phase disorder (DSWPD). The investigators will examine whether patients with DSWPD exhibit alterations in circadian rhythms and sensitivity to light compared to healthy controls. The investigators will also test a new method of predicting circadian rhythms form a blood sample.
Detailed description
- The research parts of the study are 6.5 weeks long and the study, including screening visits, involves 6 in-person visits to the Boulder campus.
- If participants qualify for the study and choose to participate, there will be two visits where participants will pick up research equipment to wear at home for 1-2 weeks of ambulatory monitoring before being studied in the laboratory. The first ambulatory monitoring session is for 2 weeks and the second is one week.
- On the first ambulatory monitoring session the investigators will have participants answer questions about participant's mood and cognition.
- On both ambulatory monitoring sessions, the investigators will also ask participants to wear a blood sugar monitor and track the timing of when participants eat using a phone app. The investigators will also have participants wear a wrist worn sleep and light monitor plus a daily sleep log and Google form of when participants go to bed and wake up.
- Next will be a visit where participants will spend 66 hours (2.75 days) in the laboratory.
- While living in the lab, participants will not be aware of the time of day (e.g., no clocks, internet, cell phones), and the investigators will schedule participant's activities.
- The investigators will ask participants to remain seated in bed and awake for up to ~39 hours, with the head of the bed raised. Participants will be studied under dim light similar to candlelight.
- The investigators will frequently take saliva samples for more than 24 hours when the investigators will ask participants to stay awake. The investigators will also take four blood samples.
- The investigators will also ask participants to perform reaction time tests, tests of participant's ability to think, and to complete ratings of how participants feel multiple times each day that participants are in the lab.
- The investigators will also record participant's brain wave activity, muscle activity, eye movements, and heart rate when participants stay awake and during ~9h sleep opportunities.
- The investigators will then ask participants to sleep normally at home for ~2 weeks, followed by 1 week of ambulatory monitoring.
- Finally, there will be a visit where participants will spend 48 hours (2 days) in the laboratory.
- While living in the lab, participants will not be aware of the time of day (e.g., no clocks, internet, cell phones) and the investigators will schedule participant's activities.
- The investigators will expose participants to different light levels (dim light similar to candlelight and typical room light).
- The investigators will frequently take saliva samples.
- The investigators will also ask participants to perform reaction time tests, tests of participant's ability to think, and to complete ratings of how participants feel multiple times each day that participants are in the lab.
- The investigators will also record participant's brain wave activity, muscle activity, eye movements, and heart rate when participants are awake and while participants sleep.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Assessment | Experimental | Behavioral: Circadian rhythm assessment, Behavioral: Light sensitivity assessmentCircadian rhythms and light sensitivity |
Who may qualify
- Ages
- 16 to 40 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult
Key inclusion criteria (3 listed)
- Delayed sleep wake phase disorder diagnosis
- Altitude history: currently residing at Denver altitude or higher
- BMI normal to moderately overweight
Key exclusion criteria (4 listed)
- Recent medical condition
- Psychiatric disorder
- Sleep disorder
- Medication use
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Circadian rhythm assessmentParticipants will arrive approximately 8 hours before participant's scheduled bedtime to practice ability to think testing and a 9-hour sleep study. Participants will live in the laboratory for approximately 66 hours (2.75 days). Upon awakening in the morning, participants will start a routine of up to 39 hours of wakefulness, under bedrest conditions. Saliva will be sampled frequently and blood will be drawn 3 times. Reaction time, ability to think, and subjective rating tests will be performed frequently. Participants will be provided scheduled bathroom breaks when participants will use a commode next to the bed. Outside these scheduled bathroom breaks, participants will be provided a bedpan to use to go to the bathroom. At the end of the research procedures for Visit 4 participants will be given a recovery sleep opportunity and be discharged from the lab in the morning near participant's typical waketime. | Behavioural | Assessment |
| Light sensitivity assessmentParticipants will arrive in the afternoon to practice ability to think testing and a 9-hour sleep study. Participants will live in the laboratory for approximately 48 hours (2 days). Upon awakening in the morning, participants will be exposed to dim candlelight and then later in the day alternating intensities of dim and room light when we keep participants awake for up to 23 hours (We will ask participants to remain in bed seated for ~12.5 hours). Saliva will be sampled frequently. Reaction time, ability to think, and subjective rating tests will be performed frequently. Participants will then have a second 9-hour sleep opportunity. | Behavioural | Assessment |
Primary outcome
Core body temperature
Time frame: Continuously for 1. up to 39 and 2. 23 hours
Body temperature measured with a pill
Glucose
Time frame: Continuously for 1. up to 39 and 2. 23 hours
Blood sugar levels
Subjective sleepiness
Time frame: Every 2 hours
Self reported sleepiness
Psychomotor vigilance
Time frame: Every 2 hours
Attention/Vigilance performance
2 secondary outcomes
Skin temperature
Time frame: Continuously for 1. up to 39 and 2. 23 hours
Melatonin
Time frame: Hourly for 1. up to 39 hours and 2. every 20 minutes
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jun 2026.
Related trials for Delayed Sleep Phase Syndrome
RecruitingPhase 4
Lemborexant in Delayed Sleep Phase Syndrome
Delayed Sleep Phase Syndrome
Recruiting
Pupillometry in Delayed Sleep Wake Phase Disorder
Delayed Sleep-Wake Phase Disorder
RecruitingPhase 2
Correcting Circadian Rhythms to Breakthrough in Bipolar Disorder
Bipolar Disorder, Delayed Sleep-Wake Phase Disorder
RecruitingPhase 3
Evaluating the Effects of Tasimelteon Vs. Placebo in Delayed Sleep-Wake Phase Disorder (DSWPD) and the CRY1Δ11 Variant
Sleep Wake Disorders, Sleep Disorders, Circadian Rhythm
Recruiting
Sleep in Psychiatric Care (SIP): Treatment for Comorbid Delayed Sleep-Wake Phase Disorder (DSWPD)
Delayed Sleep-Wake Phase Disorder, Sleep Disorder
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Kenneth Wright, PhD principal investigator
University of Colorado, Boulder
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Circadian rhythm assessment and Light sensitivity assessment in people with Delayed Sleep Phase Syndrome and Delayed Sleep Phase, run by University of Colorado, Boulder at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 17 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Kenneth Wright, PhD (303-735-1923, sleep.study@colorado.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Core body temperature (time frame: Continuously for 1. up to 39 and 2. 23 hours). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Jun 2026.