Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625001009404
Ethics application status
Approved
Date submitted
28/08/2025
Date registered
11/09/2025
Date last updated
11/09/2025
Date data sharing statement initially provided
11/09/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Assessing the impact of short-course Zopiclone on Continuous Positive Away Pressure (CPAP) effectiveness for people with Obstructive Sleep Apnoea (OSA) who wake easily
Scientific title
Assessing the impact of a physiology-informed proof-of-concept study on OSA severity with CPAP therapy in people with a low respiratory arousal threshold (ZSTOPOSA)
Secondary ID [1] 315092 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obstructive Sleep Apnoea 338489 0
Insomnia 338490 0
Condition category
Condition code
Respiratory 334794 334794 0 0
Sleep apnoea
Mental Health 334795 334795 0 0
Other mental health disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Zopiclone (7.5mg) each night for 4-weeks (30 days) in conjunction with CPAP initiation.

Timing of dosage: To be taken within 30 minutes prior to CPAP initiation each night.
Mode of administration: Oral tablet.
Intervention code [1] 331707 0
Treatment: Drugs
Comparator / control treatment
Placebo (pregelatinised maize starch) each night for 4-weeks (30 days) in conjunction with CPAP initiation.

Timing of dosage: To be taken within 30 minutes prior to CPAP initiation each night.
Mode of administration: Oral tablet.
Control group
Placebo

Outcomes
Primary outcome [1] 342431 0
Residual estimated apnea/hypopnea index (rAHI)
Timepoint [1] 342431 0
2-week baseline and 1-month after CPAP initiation
Secondary outcome [1] 450787 0
CPAP compliance - average nightly usage.
Timepoint [1] 450787 0
2-week baseline, post-treatment (1-month after CPAP initiation)
Secondary outcome [2] 451858 0
CPAP compliance - number of nights of CPAP use
Timepoint [2] 451858 0
2-week baseline, post-treatment (1-month after CPAP initiation)

Eligibility
Key inclusion criteria
Participants must be aged 18 years and older with newly diagnosed OSA (AHI>10 or more events/hr) confirmed by polysomnography (PSG) scored using standard criteria. Participants must also have a low respiratory arousal threshold confirmed via in-laboratory or home-based (level 2) PSG. All participants will be untreated for their OSA and must be willing to try CPAP and take either zopiclone or placebo nightly for 1-month.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Any medications known to effect sleep, breathing or muscle activity, pregnant or nursing mothers, any known allergy to zopiclone or previous adverse effects to zopiclone.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
allocation involved contacting the holder of the allocation schedule who was "off-site" or at central administration site.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Permuted block randomisation
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
29/09/2025
Actual
Date of last participant enrolment
Anticipated
26/10/2026
Actual
Date of last data collection
Anticipated
30/11/2026
Actual
Sample size
Target
34
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 319663 0
Charities/Societies/Foundations
Name [1] 319663 0
Flinders Foundation
Country [1] 319663 0
Australia
Primary sponsor type
University
Name
Flinders University
Address
Country
Australia
Secondary sponsor category [1] 322340 0
None
Name [1] 322340 0
Address [1] 322340 0
Country [1] 322340 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 318227 0
Southern Adelaide Clinical Human Research Ethics Committee
Ethics committee address [1] 318227 0
Ethics committee country [1] 318227 0
Australia
Date submitted for ethics approval [1] 318227 0
07/04/2025
Approval date [1] 318227 0
27/06/2025
Ethics approval number [1] 318227 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 143498 0
Prof Danny Eckert
Address 143498 0
Flinders Health and Medical Research Institute: Sleep Health. Mark Oliphant Building, 5 Laffer Drive, Bedford Park, SA, 5042
Country 143498 0
Australia
Phone 143498 0
+61 8 7421 9780
Fax 143498 0
Email 143498 0
[email protected]
Contact person for public queries
Name 143499 0
A/Prof Nicole Lovato
Address 143499 0
Flinders Health and Medical Research Institute: Sleep Health. Mark Oliphant Building, 5 Laffer Drive, Bedford Park, SA, 5042
Country 143499 0
Australia
Phone 143499 0
+61 8 72218307
Fax 143499 0
Email 143499 0
[email protected]
Contact person for scientific queries
Name 143500 0
A/Prof Nicole Lovato
Address 143500 0
Flinders Health and Medical Research Institute: Sleep Health. Mark Oliphant Building, 5 Laffer Drive, Bedford Park, SA, 5042
Country 143500 0
Australia
Phone 143500 0
+61 8 72218307
Fax 143500 0
Email 143500 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.