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Trial registered on ANZCTR


Registration number
ACTRN12625000757415
Ethics application status
Approved
Date submitted
13/06/2025
Date registered
17/07/2025
Date last updated
17/07/2025
Date data sharing statement initially provided
17/07/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Effect of Small Particle Size Bronchodilator Aerosol on Small Airway Function in Asthma
Scientific title
Targeting peripheral airway dysfunction with small particle bronchodilator in adults with asthma
Secondary ID [1] 314632 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 337796 0
Condition category
Condition code
Respiratory 334143 334143 0 0
Asthma

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Study design
This is a cross-over study. All subjects will receive both small and large particle bronchodilator, thereby serving as their own control. They will attend for 2 visits. 1x small particle visit and 1 x large particle visit. Consecutive participants will alternate between small particle first / large particle second and large particle first / small particle second, so that the order will be split equally amongst the cohort. Baseline physiology and response to both large and small particle bronchodilator will be assessed for each participant.

Bronchodilator administration
Bronchodilators act on receptors in the airway to relax the smooth muscle, increasing the airway lumen diameter, and reducing airflow obstruction. Short acting beta-2 agonists (SABA) are fast acting bronchodilators and are used as ‘rescue medication’ on presentation of asthma symptoms.

Currently there are many devices that can be used to administer SABA, which deliver particles of different sizes, but there is no consensus on which provides the most therapeutic benefit.

Up to a 100µg dose of salbutamol (equivalent of 1 actuation from a metered dose inhaler) will be delivered to the participant in the sitting position from a Aerogen Solo that will deliver the large aerosol and Aerogen PDAP nebuliser that will deliver fine aerosol (intervention).

Both the Solo and PDAP are attached to a mouthpiece, through which the participant will inhale the aerosol. They will breath normally until all of the aerosol has been delivered, this will be 1 day apart. Efficacious period for SABA / salbutamol is 4 hours, therefore 1 day is sufficient for washout.


Study setting
The study site is the Alfred Hospital. The Alfred Hospital is a large, tertiary academic hospital located in Melbourne, Australia, and is part of Alfred Health. Recruitment will be via the Asthma clinic, patients under the management of the Asthma clinic may be invited in person or over the phone to take part. Participant testing and data storage will be onsite at the Alfred hospital.
Intervention code [1] 331271 0
Treatment: Devices
Comparator / control treatment
Intervention = small particle bronchodilator delivered by specialist nebuliser (Aeroegen PDAP)
Comparator = standard size particle bronchodilator delivered by over the counter nebuliser (Aerogen Solo)
Control group
Active

Outcomes
Primary outcome [1] 341799 0
Airflow obstruction
Timepoint [1] 341799 0
Assessment will be at the end of each visit after medication delivery.
Primary outcome [2] 342196 0
Airflow obstruction
Timepoint [2] 342196 0
Assessment will be at the end of each visit after medication delivery.
Primary outcome [3] 342195 0
Airflow obstruction
Timepoint [3] 342195 0
Assessment will be at the end of each visit after medication delivery.
Secondary outcome [1] 449900 0
**Additional primary outcome** Global Ventilation heterogeneity
Timepoint [1] 449900 0
Assessment will be at the end of each visit after medication delivery.
Secondary outcome [2] 449898 0
**Additional primary outcome** Respiratory mechanics
Timepoint [2] 449898 0
Assessment will be at the end of each visit after medication delivery.
Secondary outcome [3] 449899 0
**Additional primary outcome** Respiratory mechanics
Timepoint [3] 449899 0
Assessment will be at the end of each visit after medication delivery.
Secondary outcome [4] 449905 0
Ventilation defect percentage (VDP)
Timepoint [4] 449905 0
Assessment will be at the end of each visit after medication delivery.
Secondary outcome [5] 449906 0
Spatial Ventilation heterogeneity
Timepoint [5] 449906 0
Assessment will be at the end of each visit after medication delivery.

Eligibility
Key inclusion criteria
• Able to provide informed consent to participate in the study
• Physician diagnosis of asthma
• Evidence of airway dysfunction / suboptimal Asthma control defined as either: recent positive response to salbutamol on spirometry bronchodilator testing (within 6 weeks) or an Asthma Control Questionnaire (ACQ) score >1.5.
• 18–60 years of age
• Current Non-smokers with <10-year pack history and no smoking for 12 months
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
• COPD, bronchiectasis, and any other lung disease apart from asthma based on clinical grounds and available HRCT scans
• Asthma exacerbation (increase in asthma symptoms >2days resulting in increased SABA +/- ICS or oral steroids) within the previous 6 weeks
• Attending emergency department or GP for worsening asthma symptoms in the last 12 weeks
• Current smoking (>1 cigarette/day>3months) within the last 12 months, or >10 pack year history of smoking.
• Pregnant or breastfeeding
• Unable to provide written informed consent
• Allergy to salbutamol

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



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

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 319193 0
Commercial sector/Industry
Name [1] 319193 0
Chiesi
Country [1] 319193 0
Australia
Primary sponsor type
Government body
Name
Alfred Health
Address
Country
Australia
Secondary sponsor category [1] 321660 0
None
Name [1] 321660 0
Address [1] 321660 0
Country [1] 321660 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 317775 0
Alfred Hospital Ethics Committee
Ethics committee address [1] 317775 0
Ethics committee country [1] 317775 0
Australia
Date submitted for ethics approval [1] 317775 0
19/02/2025
Approval date [1] 317775 0
03/04/2025
Ethics approval number [1] 317775 0
41/25

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

Contacts
Principal investigator
Name 142106 0
Dr Andrew Gillman
Address 142106 0
Respiratory Medicine, Alfred Health, 55 Commercial Rd, Prahran, 3004, VIC
Country 142106 0
Australia
Phone 142106 0
+61 407339127
Fax 142106 0
Email 142106 0
Contact person for public queries
Name 142107 0
Claire O'Sullivan
Address 142107 0
Lung Function, Alfred Health, 55 Commercial Rd, Prahran, 3004, VIC
Country 142107 0
Australia
Phone 142107 0
+61 03 9076 3476
Fax 142107 0
Email 142107 0
Contact person for scientific queries
Name 142108 0
Claire O'Sullivan
Address 142108 0
Lung Function, Alfred Health, 55 Commercial Rd, Prahran, 3004, VIC
Country 142108 0
Australia
Phone 142108 0
+61 03 9076 3476
Fax 142108 0
Email 142108 0

Data sharing statement
Will the study consider sharing individual participant data?
No
No IPD sharing reason/comment: Data storage and sharing has already been outlined in the submission to ethics and in the PICF. At request an amendment may be submitted to allow for further data sharing.



What supporting documents are/will be available?

TypeCitationLinkEmailOther DetailsAttachment
Study protocol    PROPOSAL_V1.0_30.01.25.pdf
Informed consent form    PICF_V2.2_17.04.25_clean.docx


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.