Sleep ApnoeaPhase 2/3TIRZE-PAPNCT07846865
Tirzepatide Versus Positive Airway Pressure for the Treatment of Obstructive Sleep Apnoea
A Phase 2/3 study testing Continuous Positive Airway Pressure and Tirzepatide in people with Sleep Apnoea and Obesity & Overweight, run by Woolcock Institute of Medical Research at 1 site in Australia.
Trial summary
When used, continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA), a condition that is mainly caused by overweight and obesity. However, CPAP is plagued by poor adherence and high rates of discontinued use leaving most patients undertreated and at risk of serious health… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Sleep Apnoea, Obesity & Overweight, Sleep Apnea Syndrome, Obstructive
- What is being tested?
- Continuous Positive Airway Pressure and Tirzepatide
- Type of treatment
- Injection or infusion, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 256 participants
- Where
- 1 siteAustralia
- Study dates
- 1 Oct 2026to 1 Dec 2028
- Phase
- Phase 2/3
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Females and Males aged ≥ 18 years at the time of signing informed consent
- Moderate-severe OSA defined as an AHI ≥ 15/hr determined from a Type 1 or 2 sleep study conducted within the previous 12 months with a clinician recommendation for CPAP therapy.
- Moderate overweight or obesity defined as BMI ≥ 27 kg/m2. (Adjusted to BMI ≥ 25 kg/m2 for Asian populations as per WHO guidelines (WHO Expert Consultation (2004))
- No contraindication to tirzepatide use as per Australian Product Information
- Home internet access to enable cloud storage of SleepTracker-AI in-home BDI.
- Fluent English literacy and able to provide informed consent.
Who cannot join
- OSA or other respiratory related criteria:
- Respiratory failure including obesity hypoventilation syndrome (OHS) or daytime hypercapnia or moderate-severe chronic obstructive pulmonary disease (COPD) with FEV1/FVC ratio<0.7 and FEV1<80% predicted (GOLD criteria).
- Driver occupation with excessive sleepiness (Epworth Sleepiness Scale >=16) or sleepiness-related motor vehicle accident or near accident within 12 months prior to enrolment
- Current or prior (≤3 months) OSA treatment with mechanical therapy (CPAP, MAS, Positional)
- >50% respiratory events with Cheyne-Stokes Respiration (CSR) or Central Sleep Apnoea (CSA)
- Relative or absolute contraindication to CPAP including chronic cranial injury; recurrent pneumothorax; indication for oral-pharyngeal surgery, significant craniofacial abnormalities that may affect breathing, or are unwilling to use CPAP
Show all 18Show fewer
- Any previous or planned surgery for OSA or major ear, nose or throat surgery, including tonsillectomy and adenoidectomy that still may affect breathing (NB: Inclusion of a participant with more minor ear, nose or throat surgery (for example, deviated septum) will be at the investigator's discretion)
- Glycaemia related criteria:
- HbA1c ≥ 48 mmol/mol (6.5%) at screening
- Type 1 or type 2 diabetes mellitus
- Treatment with glucose-lowering agent(s) within 90 days before screening
- Treatment with a GLP-1 receptor agonist within 90 days before screening
- Obesity related criteria:
- A self-reported change in body weight >5 kg or >5% within 90 days before baseline
- Treatment with medication for the indication of obesity within 90 days before baseline and/or currently enrolled in a weight loss program
- Other criteria:
- Pregnancy/breast feeding or planning a pregnancy during the trial period
- Relative or absolute contraindication to tirzepatide including needle phobia
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Julia Chapman, PhD contact
Australia1 site
Woolcock Institute of Medical Research
Macquarie Park, New South Wales, 2113
Greg Kaplan, PhD, +61 2 9805 3232, grigori.kaplan@woolcock.org.au
About this study
Official title: Tirzepatide Versus Positive Airway Pressure for the Treatment of Obstructive Sleep Apnoea: A Randomised Comparative Effectiveness Trial
When used, continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA), a condition that is mainly caused by overweight and obesity. However, CPAP is plagued by poor adherence and high rates of discontinued use leaving most patients undertreated and at risk of serious health complications. This study aims to test whether new effective weight loss pharmacotherapy is superior to CPAP for alleviating OSA and improving health outcomes.
Read the detailed description
The TIRZE-PAP study is a parallel randomised superiority trial comparing weight loss with weekly tirzepatide (15mg or the maximum tolerated dose) versus CPAP, in 256 people with moderate-severe OSA (AHI≥15/hr) and overweight or obesity (BMI: ≥27kg/m2). Participants allocated to CPAP will receive therapy as per usual care by their treating physician. Participants allocated to tirzepatide will undergo a 20-week stepped titration with a monthly increase of dose to a maximum 15mg (or maximum tolerated) by week 20. Outcomes will be collected over two 28-day periods commencing at baseline (pre-intervention weeks -4 to 0) and at follow-up (post-intervention weeks 48 to 52).
- Being tested
- Continuous Positive Airway Pressure, Tirzepatide
- Keywords
- Continuous Positive Airway Pressure, Tirzepatide, Sleep Apnoea, Clinical Trial, weight loss, GLP1, Mounjaro, OSA, CPAP, comparative effectiveness, randomized, sleep apnea, GIP
- Medical subject headings
- Sleep Apnea Syndromes, Obesity, Overweight, Sleep Apnea, Obstructive, Weight Loss
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Continuous Positive Airway PressureDevice
CPAP will be set at a fixed pressure that abolishes apnoeas and hypopneas determined from an in-lab titration study or set according to a pre-determined algorithm using an auto-titrating machine at home.
Participants may also be counselled on losing weight with diet and exercise as per usual practice.
TirzepatideDrug
Patients allocated to weight loss with tirzepatide will be managed by the study dietitian. The tirzepatide formulation is administered subcutaneously once weekly using single-use injection pens. Participants will undergo a 20-week dose escalation phase (starting at 2.5mg/week for 4 weeks, 5 mg/week for 4 weeks, 7.5mg/week for 4 weeks, 10mg/week for 4 weeks, 12.5mg/week for 4 weeks) followed by a dose maintenance phase of 15mg/week for the remainder of the 12-month study period. Participants unable to tolerate the next highest dose will be maintained on the maximum tolerable dose for the duration of the intervention.
| Study group | Role | What they receive |
|---|---|---|
| Continuous Positive Airway Pressure (CPAP) | Active comparator | Not described Receives: Device: Continuous Positive Airway Pressure |
| Tirzepatide | Experimental | Not described Receives: Drug: Tirzepatide |
What is being measured
The primary outcome is the main question the study is designed to answer.
Breathing Disturbance Index (BDI)
BDI is the primary severity metric of OSA in the trial which is measured by the number of breathing disturbances per hour of sleep. This is measured using contactless mattress-based OSA monitors (SleepTracker-AI) that can automatically and reliably measure true OSA alleviation every night for the entire period of sleep.
Measured: The mean BDI measured over 28 nights of monitoring is calculated for baseline (Weeks -4 to 0) and follow-up (Weeks 48 to 52)
Secondary outcomes (6)
Hypoxia - Oxygen Desaturation Index (ODI 3%)
ODI 3% is calculated as the number of oxygen desaturation events ≥3% per hour as a percentage of time in bed, estimated using at-home oximetry (RingConn Gen 2).
Measured: ODI 3% will be determined as a mean of 7-10 nights of data acquired at baseline and a mean of 7-10 nights of data acquired at 12month follow-up.
Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep-Related Impairment Short Form 8a Score
The Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep-Related Impairment Short Form 8a Score is used to assess participant-reported levels of alertness, sleepiness, and tiredness and the functional impairments associated with sleep problems or reduced alertness over the past 7 days. Impairment ranges from a minimum of 5 (no impairment) to a maximum of 40 (maximal impairment).
Measured: Collected at Baseline and 3,6,9 and 12 months.
Epworth Sleepiness Scale (ESS)
The Epworth Sleepiness Scale (ESS) measures self-reported subjective sleepiness using an 8-item questionnaire. Sleepiness ranges from a minimum of 0 (no sleepiness) to a maximum of 24 (severe sleepiness).
Measured: Collected at Baseline and 3,6,9 and 12 months.
Ambulatory Blood Pressure - Sleep Systolic Blood Pressure (SBP)
Sleep SBP is measured hourly, using an ambulatory blood pressure monitor, for a self-reported sleep period.
Measured: Baseline and Week 52
Cardiometabolic Fasted Blood Markers - Low-Density Lipoproteins (LDL)
Low-density lipoproteins are measured from fasted venous blood.
Measured: Screening and Week 52
Cardiometabolic Fasted Blood Markers - HbA1c
HbA1c, or glycated haemoglobin, assesses long-term glycaemic control. It is measured from fasted venous blood.
Measured: Screening and Week 52
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Sep 2026
- Study start1 Oct 2026 (estimated)
- Primary completion1 Dec 2028 (estimated)
- Study completion1 Dec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Sleep ApnoeaStudies 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 2/3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 256 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Woolcock Institute of Medical Research
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Craig Phillips, Woolcock Institute of Medical Research
- Investigators
- Craig Phillips, Principal investigator, Woolcock Institute of Medical Research and Macquarie Medical School, Macquarie University, Sydney, NSW, AustraliaRon Grunstein, Principal investigator, Woolcock Institute of Medical Research and Macquarie Medical School, Macquarie University, Sydney, NSW, AustraliaCamilla Hoyos, PhD, Study chair, Woolcock Institute of Medical Research
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07846865
- Sponsor's protocol ID
- 20081
- Acronym
- TIRZE-PAP
- Status last verified
- Oct 2026
- First submitted
- 22 Sep 2026
- Last updated
- 2 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Non-identifiable IPD will be shared upon reasonable request to the Principal Investigators.
Study at a glance
From the registry record, last updated by the sponsor on 2 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Tirzepatide Versus Positive Airway Pressure for the Treatment of Obstructive Sleep Apnoea: A Randomised Comparative Effectiveness Trial
- ClinicalTrials.gov ID
- NCT07846865
- Acronym / sponsor ID
- TIRZE-PAP / 20081
- Keywords
- Continuous Positive Airway Pressure, Tirzepatide, Sleep Apnoea, Clinical Trial, weight loss, GLP1, Mounjaro, OSA
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 256 participants (estimated)
- Lead sponsor
- Woolcock Institute of Medical ResearchUniversity, hospital or other
- Study start
- 1 Oct 2026 (estimated)
- Primary completion
- 1 Dec 2028 (estimated)
- Study completion
- 1 Dec 2028 (estimated)
- First posted
- 29 Sep 2026 (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.
When used, continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA), a condition that is mainly caused by overweight and obesity. However, CPAP is plagued by poor adherence and high rates of discontinued use leaving most patients undertreated and at risk of serious health complications. This study aims to test whether new effective weight loss pharmacotherapy is superior to CPAP for alleviating OSA and improving health outcomes.
Detailed description
The TIRZE-PAP study is a parallel randomised superiority trial comparing weight loss with weekly tirzepatide (15mg or the maximum tolerated dose) versus CPAP, in 256 people with moderate-severe OSA (AHI≥15/hr) and overweight or obesity (BMI: ≥27kg/m2). Participants allocated to CPAP will receive therapy as per usual care by their treating physician. Participants allocated to tirzepatide will undergo a 20-week stepped titration with a monthly increase of dose to a maximum 15mg (or maximum tolerated) by week 20. Outcomes will be collected over two 28-day periods commencing at baseline (pre-intervention weeks -4 to 0) and at follow-up (post-intervention weeks 48 to 52).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Continuous Positive Airway Pressure (CPAP) | Active comparator | Device: Continuous Positive Airway Pressure |
| Tirzepatide | Experimental | Drug: Tirzepatide |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Females and Males aged ≥ 18 years at the time of signing informed consent
- Moderate-severe OSA defined as an AHI ≥ 15/hr determined from a Type 1 or 2 sleep study conducted within the previous 12 months with a clinician recommendation for CPAP therapy.
- Moderate overweight or obesity defined as BMI ≥ 27 kg/m2. (Adjusted to BMI ≥ 25 kg/m2 for Asian populations as per WHO guidelines (WHO Expert Consultation (2004))
- No contraindication to tirzepatide use as per Australian Product Information
- Home internet access to enable cloud storage of SleepTracker-AI in-home BDI.
Key exclusion criteria (18 listed)
- Respiratory failure including obesity hypoventilation syndrome (OHS) or daytime hypercapnia or moderate-severe chronic obstructive pulmonary disease (COPD) with FEV1/FVC ratio<0.7 and FEV1<80% predicted (GOLD criteria).
- Driver occupation with excessive sleepiness (Epworth Sleepiness Scale >=16) or sleepiness-related motor vehicle accident or near accident within 12 months prior to enrolment
- Current or prior (≤3 months) OSA treatment with mechanical therapy (CPAP, MAS, Positional)
- >50% respiratory events with Cheyne-Stokes Respiration (CSR) or Central Sleep Apnoea (CSA)
- Relative or absolute contraindication to CPAP including chronic cranial injury; recurrent pneumothorax; indication for oral-pharyngeal surgery, significant craniofacial abnormalities that may affect breathing, or are unwilling to use CPAP
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 |
|---|---|---|
| Continuous Positive Airway PressureCPAP will be set at a fixed pressure that abolishes apnoeas and hypopneas determined from an in-lab titration study or set according to a pre-determined algorithm using an auto-titrating machine at home. Participants may also be counselled on losing weight with diet and exercise as per usual practice. | Device | Continuous Positive Airway Pressure (CPAP) |
| TirzepatidePatients allocated to weight loss with tirzepatide will be managed by the study dietitian. The tirzepatide formulation is administered subcutaneously once weekly using single-use injection pens. Participants will undergo a 20-week dose escalation phase (starting at 2.5mg/week for 4 weeks, 5 mg/week for 4 weeks, 7.5mg/week for 4 weeks, 10mg/week for 4 weeks, 12.5mg/week for 4 weeks) followed by a dose maintenance phase of 15mg/week for the remainder of the 12-month study period. Participants unable to tolerate the next highest dose will be maintained on the maximum tolerable dose for the duration of the intervention. | Drug | Tirzepatide |
Primary outcome
Breathing Disturbance Index (BDI)
Time frame: The mean BDI measured over 28 nights of monitoring is calculated for baseline (Weeks -4 to 0) and follow-up (Weeks 48 to 52)
BDI is the primary severity metric of OSA in the trial which is measured by the number of breathing disturbances per hour of sleep. This is measured using contactless mattress-based OSA monitors (SleepTracker-AI) that can automatically and reliably measure true OSA alleviation every night for the entire period of sleep.
6 secondary outcomes
Hypoxia - Oxygen Desaturation Index (ODI 3%)
Time frame: ODI 3% will be determined as a mean of 7-10 nights of data acquired at baseline and a mean of 7-10 nights of data acquired at 12month follow-up.
Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep-Related Impairment Short Form 8a Score
Time frame: Collected at Baseline and 3,6,9 and 12 months.
Epworth Sleepiness Scale (ESS)
Time frame: Collected at Baseline and 3,6,9 and 12 months.
Ambulatory Blood Pressure - Sleep Systolic Blood Pressure (SBP)
Time frame: Baseline and Week 52
Cardiometabolic Fasted Blood Markers - Low-Density Lipoproteins (LDL)
Time frame: Screening and Week 52
Cardiometabolic Fasted Blood Markers - HbA1c
Time frame: Screening and Week 52
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 2 Nov 2026.
- Individual participant dataSharing planned: Yes. Non-identifiable IPD will be shared upon reasonable request to the Principal Investigators.
Related trials for Sleep Apnoea
RecruitingObservational study
Locus Coeruleus and CCHS (Congenital Central Hypoventilation Syndrome)
Ondine Syndrome (Congenital Central Hypoventilation Syndrome)
RecruitingObservational study
Development and Validation of a Multimodal Deep Learning Model Using Peripheral Oxygen Saturation and Ballistocardiography Signals for Predicting Apnea-Hypopnea Index in Obstructive Sleep Apnea
Obstructive Sleep Apnea
Not yet recruiting
Comprehensive Opioid Management and Breathing During Sleep
Sleep-Disordered Breathing, Chronic Opioid Use
Recruiting
Janus II Feasibility
Sleep Apnea
RecruitingPhase 3
A Study to Learn About the Monthly Dosing Study Medicine Called Berobenatide in Adults With Breathing Problems During Sleep and Overweight or Obesity Who Do Not Use a Breathing Machine (PAP) (VESPER-OSA 2)
Apnea, Sleep Disorders
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.
Julia Chapman, PhD contact
Craig Phillips principal investigator
Woolcock Institute of Medical Research and Macquarie Medical School, Macquarie University, Sydney, NSW, Australia
Ron Grunstein principal investigator
Woolcock Institute of Medical Research and Macquarie Medical School, Macquarie University, Sydney, NSW, Australia
Camilla Hoyos, PhD study chair
Woolcock Institute of Medical Research
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Continuous Positive Airway Pressure and Tirzepatide in people with Sleep Apnoea and Obesity & Overweight, run by Woolcock Institute of Medical Research at 1 site in Australia.
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 6 inclusion and 18 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: opening soon, as of the sponsor's last update on 2 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Australia. 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.
What does this combined phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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 Craig Phillips, PhD (02 9805 3000, c.phillips@mq.edu.au), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Breathing Disturbance Index (BDI) (time frame: The mean BDI measured over 28 nights of monitoring is calculated for baseline (Weeks -4 to 0) and follow-up (Weeks 48 to 52)). 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 2 Nov 2026.