KPAP Adherence Crossover Study

May 4, 2026 updated by: SleepRes Inc.

A Prospective, Randomized, Crossover Study of Therapy Adherence With Kairos Positive Airway Pressure (KPAP) Compared to Automatic Adjusting Positive Airway Pressure (APAP) for the Treatment of Obstructive Sleep Apnea (OSA)

A device able to provide less positive airway pressure (PAP) for the entire duration of inspiration and roughly half the duration of expiration, designated KPAP, is being developed by SleepRes for the treatment of obstructive sleep apnea (OSA). In prior studies, the administration of higher inspiratory than expiratory PAP did not substantially increase treatment efficacy or adherence to continuous PAP (CPAP), which remains low. In our recent investigation, we demonstrated that the addition of a resistor to the CPAP circuit to reduce inspiratory PAP increased subjective comfort. In another study, we showed that KPAP improved subjective comfort during wakefulness vs. fixed CPAP, while maintaining treatment efficacy. The present study, KPAP Adherence 1, is a randomized, crossover study designed to examine whether KPAP can improve adherence over APAP as an at home treatment for OSA.

Study Overview

Status

Not yet recruiting

Intervention / Treatment

Detailed Description

The KPAP Adherence 1 is a randomized, crossover study in which the adherence to therapy will be compared between KPAP and standard APAP. Participants will be chosen from a pool of patients who are PAP-naïve and who have received either a PSG (in-lab polysomnogram), split-night study (in-lab PSG and pressure titration) or home sleep study (HST) within the previous 3 months.

Upon signing an informed consent, participants will be randomly assigned to start on either the KPAP (supplied by a SleepRes device) or the APAP (supplied by a ResMed device) arm when they arrive at the office. Each participant will then be given their new equipment and will be trained in proper use of the device assigned for the first treatment arm. The device will be used at home, nightly, for 4 weeks. Afterward, they will return to the office for their second visit. They will then be given the other device-along with the appropriate explanation on how to use it-that they will use on their second treatment arm. Subsequently, they will undergo a washout period of 1 week where no therapy will be used. Following the washout period, they will initiate another 4-week usage with the second therapy device. At the end of the second 4-week period, participants will return to the office for their third visit.

In both the APAP and KPAP arms, participants will have their therapy set to 5-20 cmH2O for one week. The pressure range will then be narrowed to ± 2 cmH2O around their 95% pressure level as assessed during the first week. This same pressure range will be used during the second arm for each patient.

During the KPAP arm, participants will be set to a double Comfort Setting drop according to the following scheme. This drop schedule will be implemented while the KPAP device is operating with automatic pressure adjustment.

Pset Drop 1 Drop 2 5.0 - 5.9 0 0 6.0 - 6.9 1 0 7.0 - 7.9 2 0 8.0 - 8.9 2 1 9.0 - 9.9 2 2 10.0 - 20.0 2 3

Phone calls to encourage use and assess adherence and side effects will be made at different time points during both treatment arms. Subjects using the device less than an average of 5 hours per night during the first week will be contacted on a more regular basis (weekly until 5 hour per night use is achieved) to address any problems and encourage use. If participants discontinue the use of the device during the home use period, they will still be encouraged to return for all testing per protocol. If a patient refuses to come in for further testing, they will be considered a lost to follow up and excluded from efficacy analysis.

  • 1 Day Phone Call (+2 days)
  • 7 Day Phone Call (+/- 3 days)
  • 14 Day Phone Call (+/- 3 days)
  • 21 Day Phone Call (+/- 3 days) to remind participants and schedule the office visit and device return on day 28
  • Equipment Return

After each arm, the patient will return to the office for the after-treatment visit (Visit 2 and Visit 3) to record the following:

  • Adverse Event Assessment
  • PROMIS Fatigue
  • Epworth Sleepiness Scale (ESS)
  • Functional Outcomes of Sleep Questionnaire (FOSQ)
  • Short Form 36 (SF36)
  • Comfort and Satisfaction, per Visual analog Scale (VAS)
  • Nightly adherence recording

Data collected from the therapy device will include the following:

  • Usage averaged over the 4-week period and nightly
  • Leak averaged over the 4-week period and nightly
  • P95 averaged over the 4-week period and nightly
  • Sleep events averaged over the 4-week period and nightly

Study Type

Interventional

Enrollment (Estimated)

30

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Tennessee
      • Murfreesboro, Tennessee, United States, 37129
        • Sleep Centers of Middle Tennessee
        • Contact:
        • Sub-Investigator:
          • Bernard Hete, PhD
        • Sub-Investigator:
          • William H Noah, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. AHI > 10 on a previous PSG or HST (hypopneas requiring 4% desaturation).
  2. Central apneas < 25% of events
  3. PLM (Periodic Limb Movements) arousal index < 15

Exclusion Criteria:

  1. A female of child-bearing potential that is pregnant or intends to become pregnant.
  2. Any unstable or severe medical condition of any organ system including congestive heart failure, COPD, renal failure, neuromuscular disease, etc., or at the discretion of the site Principal Investigator (PI).
  3. Taking medication that may affect sleep, sleepiness, or alertness including hypnotics, sedatives, alerting agents, stimulants, anticonvulsants, etc.
  4. The presence of any other sleep disorder (insomnia, periodic limb movement disorder, etc).
  5. Prior therapy or treatment for OSA.
  6. Chronic oxygen therapy.
  7. Excessive alcohol consumption (>14 drinks/week).
  8. The use of any illegal drug(s).
  9. Any condition that in the investigator's opinion would present an unreasonable risk to the participant, or which would interfere with their participation in the study or confound study interpretation.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: 4-weeks breathing on APAP
Patients will breathe on APAP for 4 weeks simulating normal therapy. Usage, leak, P95/P90 and AHI will be recorded and averaged over the duration.
Standard CPAP therapy where therapy pressure is automatically adjusted to prevent respiratory events from occurring. The TheraPAP prototype device will be used to operate in the APAP mode in addition to the TheraPAP intervention mode.
Experimental: 4-weeks breathing on KPAP
Patients will breathe on TheraPAP for 4 weeks, which is the therapy under evaluation. Usage, leak, P95/P90 and AHI will also be recorded and averaged over the duration.
TheraPAP is a novel CPAP-based therapy in which pressure is dropped as much as 5 cmH2O starting at the beginning of inspiration and extending through the end of expiration where it rises back up to the true therapy pressure for a short period. It improves comfort by providing pressure only when it is needed and maintaining it at a low level the rest of the time. Normal CPAP/APAP therapy keeps pressure at the therapy level during the entire breath cycle, except with some alternate approaches where pressure is decreased but only during the expiratory phase.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Usage
Time Frame: Averaged over every night for each 4-week arm
Number of hours for which therapy is used per night
Averaged over every night for each 4-week arm

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
ESS Questionnaire
Time Frame: Filled out twice, once after completion of each 4-week arm (at week 4 and at week 9)
Epworth Sleepiness Scale - a standard questionnaire to assess sleep quality. Scoring goes from 0 to 24 and higher scores means worsening sleepiness.
Filled out twice, once after completion of each 4-week arm (at week 4 and at week 9)
FOSQ-10 Questionnaire
Time Frame: Filled out twice, once after completion of each 4-week arm (at week 4 and at week 9)
Functional Outcomes of Sleep Questionnaire - 10 - a standard questionnaire to assess sleep quality. Scoring goes from 10 to 40 and higher scores means better functional outcome.
Filled out twice, once after completion of each 4-week arm (at week 4 and at week 9)
Excess Leak or Leak
Time Frame: Averaged over every night for each 4-week arm
Excess leak is patient circuit leak in excess of the normal leak required to prevent rebreathing in a CPAP device, which exits the circuit from the exhaust valve. Examples of excess leak include mask sealing leak or mouth opening. This excess leak will be averaged per night.
Averaged over every night for each 4-week arm
P95/P90
Time Frame: Averaged over every night for each 4-week arm
Standard CPAP measurement - pressure levels that eliminate breathing obstructions for at least 90% to 95% of the sleep period
Averaged over every night for each 4-week arm
AHI
Time Frame: Averaged over every night for each 4-week arm
Apnea/Hypopnea Index - measure of the number of obstructive breathing events per hour experienced by the patient
Averaged over every night for each 4-week arm

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Study Director: William H Noah, MD, SleepRes, LLC., Sleep Centers of Middle Tennessee, LLC

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

July 1, 2026

Primary Completion (Estimated)

December 1, 2026

Study Completion (Estimated)

December 31, 2026

Study Registration Dates

First Submitted

May 3, 2024

First Submitted That Met QC Criteria

May 8, 2024

First Posted (Actual)

May 14, 2024

Study Record Updates

Last Update Posted (Actual)

May 6, 2026

Last Update Submitted That Met QC Criteria

May 4, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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