Real-World Use of an iPad-Based Light Therapy App, With Optional Biomarker Collection

NCT07744711 | Enrolling By Invitation FDA Device

• 1 other identifier: COS-20262058
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

This study looks at how adults use an iPad-based light app in everyday life. Light is the main signal that sets the body's internal clock, which controls daily rhythms in sleep, alertness, and many other body systems. Indoor living means many people do not get bright light at a consistent time each day. The app uses the iPad screen to deliver light while people watch videos, read, or browse. It suggests about one hour of use per day, started within about two hours of waking. It does not require anyone to follow that schedule, and no one is locked out for using it more, less, or at other times. The app shows people when they are positioned to receive the intended light, records how the app is used, and asks short questions about sleep. The main questions this study aims to answer are:

1. 1.How often, how long, and at what time of day do people use the app?
2. 2.What do people mostly do during light-delivery sessions?
3. 3.What do people think of the app, and how easy is it to use?

Conditions

Circadian Rhythms

Keywords

chronotype; phototherapy; chronotherapy; photoentrainment; light therapy; real-world evidence; patterns of use; circadian medicine

Outcome Measures

Primary Outcomes (4)

• Frequency of Circadian OS app (KairOS) use

  Number of light-delivery sessions completed per participant per week, captured by in-app telemetry.

  From initiation of app use through the end of the app-exposure period, up to eight weeks

• Duration of app use: minutes of light exposure per session

  Duration in minutes of each light-delivery session, captured by in-app telemetry.

  From initiation of app use through the end of the app-exposure period, up to eight weeks

• Timing of app use relative to habitual wake time

  Start time of each light-delivery session, expressed as hours elapsed since the participant's habitual wake time, as measured by the Munich Chronotype Questionnaire completed at baseline.

  From initiation of app use through the end of the app-exposure period, up to eight weeks

• Context of app use

  Concurrent on-screen activity during light-delivery sessions, captured by in-app telemetry.

  From initiation of app use through the end of the app-exposure period, up to eight weeks

Secondary Outcomes (6)

• Participant-reported feedback on the app experience, usability, and perceived effects

  Weekly during the app-exposure period and at the end of the app-exposure period, up to eight weeks

• Self-reported sleep and circadian-rhythm parameters during the exposure period

  From initiation of app use through the end of the app-exposure period, up to eight weeks

• Drop-off and return-to-use patterns

  From initiation of app use through the end of the app-exposure period, up to eight weeks

• System Usability Scale (SUS) score

  End of Week 1 and end of the app-exposure period; a single administration is done at the end of Week 1 when the app-exposure period is one week

• Number of Use Errors Identified During App Use

  From initiation of app use through the end of the app-exposure period, up to eight weeks

Study Arms (1)

Circadian OS Light App (KairOS)

EXPERIMENTAL

Participants receive the investigational Circadian OS iPad-based light app and use it in their normal environment over a defined exposure period. App onboarding presents a recommended use envelope of approximately 60 minutes per day within approximately 2 hours of habitual wake time, anchored to the participant's Munich ChronoType Questionnaire response. Use is not enforced: the app does not lock out participants who use it less, more, or outside the recommended window, and non-use is recorded as participation data. Participants complete brief in-app check-ins on sleep and experience, plus periodic usability surveys. Optional sub-studies (actigraphy, biomarker collection, moderated human-factors observation) are independently elected by participants within this single arm.

Device: Circadian OS iPad-based light app

Interventions

Circadian OS iPad-based light app DEVICE

Software-based light-delivery platform running on an off-the-shelf iPad. The app uses the display to deliver light targeting a specified circadian stimulus (CS ≥ 0.3), integrating spectrum and intensity at the eye. It runs closed-loop: screen luminance is calibrated in advance, the iPad camera tracks viewing distance and gaze direction, and the app computes the dose reaching the eye in real time, signaling whether the user is positioned to receive it. Session start-time recommendations are anchored to each participant's habitual wake time, derived from the Munich ChronoType Questionnaire. Onboarding presents a recommended envelope of approximately 60 minutes per day within approximately 2 hours of habitual wake. Use is not enforced and the app does not lock out off-envelope use. Participants use the app while streaming, reading, or browsing as they normally would.

Also known as: KairOS, Circadian OS app

Circadian OS Light App (KairOS)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adult 18 years of age or older
• Able to read, understand, and provide written informed consent in English
• Has access to a compatible iPad capable of running the study app for the duration of the exposure period, or is willing to use a Sponsor-supplied iPad
• U.S. resident, able to be in the NYC metropolitan area for the study
• Member of the Sponsor's network (friends, family, advisors, investors, employees, or contractors)
• If opting in to the biomarker sub-study: weighs at least 110 lb (50 kg), and meets standard venipuncture eligibility on the day of collection

You may not qualify if:

• Diagnosed bipolar disorder, or history of light-induced manic or hypomanic episodes
• Pregnant, attempting to become pregnant, or breastfeeding
• Diagnosed photosensitivity disorder, retinal disease, or use of medications known to cause significant photosensitivity, at investigator discretion based on disclosed medications
• Currently using prescription light therapy, or actively enrolled in another light-related research study
• Unable to consent for themselves (participants requiring enrollment by a legally authorized representative are not eligible)
• Biomarker sub-study only: acutely unwell, febrile, or reporting acute infectious symptoms on the study day
• Biomarker sub-study only: known bleeding diathesis, anticoagulant use other than low-dose aspirin, severe needle phobia, or whole-blood or plasma donation within the prior two weeks
• Biomarker sub-study only: member of the study or laboratory team who would otherwise process their own sample
• Any condition that, in the judgment of the investigator or attending phlebotomist or nurse, would make participation unsafe

Sponsors & Collaborators

• Circadian OS, Inc: lead

Study Sites (1)

SOSV

New York, New York, 10001, United States

Location

Related Publications (4)

• Patke A, Young MW, Axelrod S. Molecular mechanisms and physiological importance of circadian rhythms. Nat Rev Mol Cell Biol. 2020 Feb;21(2):67-84. doi: 10.1038/s41580-019-0179-2. Epub 2019 Nov 25.

  PMID: 31768006 BACKGROUND

• Allada R, Bass J. Circadian Mechanisms in Medicine. N Engl J Med. 2021 Feb 11;384(6):550-561. doi: 10.1056/NEJMra1802337. No abstract available.

  PMID: 33567194 BACKGROUND

• Roenneberg T, Pilz LK, Zerbini G, Winnebeck EC. Chronotype and Social Jetlag: A (Self-) Critical Review. Biology (Basel). 2019 Jul 12;8(3):54. doi: 10.3390/biology8030054.

  PMID: 31336976 BACKGROUND

• Rea MS, Nagare R, Figueiro MG. Modeling Circadian Phototransduction: Retinal Neurophysiology and Neuroanatomy. Front Neurosci. 2021 Feb 5;14:615305. doi: 10.3389/fnins.2020.615305. eCollection 2020.

  PMID: 33613175 BACKGROUND

Study Officials

• Sofia Axelrod, PhD

  Circadian OS, Inc

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Single-arm, open-label, naturalistic device-use study. All participants receive the investigational app and use it without enforcement or lockout. Adherence to the recommended use envelope is not required, and non-use, partial weeks, and re-engagement are recorded as participation data rather than protocol deviations. Optional sub-studies (actigraphy, biomarker collection, moderated human-factors sessions) are independently elected by participants and do not constitute separate assigned arms.

Study Record Dates

• First Submitted: July 19, 2026
• First Posted: August 4, 2026
• Study Start: July 17, 2026
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): June 30, 2028
• Last Updated: August 4, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)