Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12618001362280
Ethics application status
Approved
Date submitted
10/08/2018
Date registered
14/08/2018
Date last updated
29/10/2021
Date data sharing statement initially provided
19/07/2019
Date results information initially provided
29/10/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Soluble fibre for asthma control
Scientific title
A double-blind, randomized, placebo-controlled, 4-way crossover trial investigating the effect of a soluble fibre supplement on asthma control and airway inflammation in stable asthma.
Secondary ID [1] 294289 0
None
Universal Trial Number (UTN)
U1111-1210-6727
Trial acronym
OLI 2
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 306984 0
Condition category
Condition code
Inflammatory and Immune System 306079 306079 0 0
Other inflammatory or immune system disorders
Respiratory 308092 308092 0 0
Asthma

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study is a double-blind, randomised, placebo-controlled, 4-way crossover trial including clinically stable asthmatic adults to examine the effect of a soluble fibre supplement (an oligosaccharide blend) on asthma control and airway inflammation.

There are three intervention arms and one placebo arm in this study. Each subject will be randomly allocated to take each treatment/placebo arm in random order for 2 weeks each, with a 2 week wash out period in between each phase of the study.

1. High dose formulation 1: 12 g/d of total oligosaccharides via (1x6g oligosaccharides and 1x6g placebo) dose in morning and (1x6g oligosaccharides) dose in evening.

2. High dose formulation 2: 12g total oligosaccharides via 1x12g oligosaccharides dose in morning and 1x6g placebo dose in evening.

3. Low dose formulation: 1x6g total oligosaccharides via (1x6g oligosaccharides and 1x6g placebo) in morning and 1x6g dose placebo dose in evening.

4. Placebo control: 18 g/d or equivalent weight to investigational product of maltodextrin powder via 1x12g dose in morning and 1x6g dose in evening.

The oligosaccharide blend powder and placebo powder (maltodextrin) will be provided to participants in individual sachets for each dose, to be mixed with water twice daily (morning/evening).

This study takes place over 16 weeks. Two weeks prior to the start of the study, and for the duration of the study, participants will consume a fibre controlled diet. This will include consumption of no more than 2 serves of fruits and vegetables per day and consume ½ cup of bran-based cereal per day to avoid constipation, and avoidance of other fibre-rich foods including oats, oat bran, beans, seeds and sources of probiotics such as yoghurt and fermented milk drinks. Participants will be provided with a standardized evening meal (pasta meal), which they will be asked to consume the night before each of their scheduled appointments. They will also be asked to fast for 12-hours prior to the clinic visit. Adherence with the protocol will be monitored by sachet returns and study diaries.
Intervention code [1] 300587 0
Treatment: Other
Comparator / control treatment
Control treatment: Placebo (18 g/d or equivalent weight to investigational product of maltodextrin powder via 1x12g dose in morning and 1x6g dose in evening) for 2 weeks.

Comparator treatments: Oligosaccharide blend at a high dose formulation 1 (12 g/d of total oligosaccharides via [1x6g oligosaccharides and 1x6g placebo] dose in morning and [1x6g oligosaccharides] dose in evening, high dose formulation 2 (12g total oligosaccharides via 1x12g oligosaccharides dose in morning and 1x6g placebo dose in evening), and low dose formulation (1x6g total oligosaccharides via [1x6g oligosaccharides and 1x6g placebo] in morning and 1x6g dose placebo dose in evening).
Control group
Placebo

Outcomes
Primary outcome [1] 305114 0
Asthma Control as measured by the Juniper Asthma Control Questionnaire (ACQ7)
Timepoint [1] 305114 0
Change in asthma control after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [1] 344200 0
Airway inflammation as measured by sputum cell counts.
Timepoint [1] 344200 0
Change in sputum cell counts after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [2] 344201 0
Lung function as measured by spirometry (FEV1 and FVC).
Timepoint [2] 344201 0
Change in lung function after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [3] 344202 0
Airway hyper-responsiveness determined by saline challenge.
Timepoint [3] 344202 0
Change in airway hyper-responsiveness after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [4] 344203 0
Plasma short chain fatty acids (SCFA) as measured by gas chromatography.
Timepoint [4] 344203 0
Change in SCFA after two weeks of each treatment arm compared to placebo.
Secondary outcome [5] 344204 0
Gastrointestinal symptoms as assessed by the Gastrointestinal Symptoms Rating Scale scores (GSRS) (modified).
Timepoint [5] 344204 0
Change in GSRS scores after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [6] 344208 0
Faecal microbiota - exploratory analysis
Timepoint [6] 344208 0
Change in faecal microbiota after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [7] 345567 0
General Quality of life as measured by the 36-Item Short Form Survey Instrument (SF-36)
Timepoint [7] 345567 0
Change in SF-36 after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [8] 345568 0
Quality of Life assessed by the Asthma Quality of Life Questionnaire (AQLQ)
Timepoint [8] 345568 0
Change in AQLQ after 2 weeks of each treatment arm compared to placebo.
Secondary outcome [9] 350559 0
Airway inflammation as measured by exhaled nitric oxide (eNO).
Timepoint [9] 350559 0
Change in eNO after 2 weeks of each treatment arm compared to placebo.

Eligibility
Key inclusion criteria
Males and females aged 18 years and over.
Doctor diagnosis of asthma and confirmed airway hyper-responsiveness
Poorly controlled asthma, defined as ACQ6 >0.75 units
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Recent (past month) respiratory tract infection; respiratory conditions other than asthma; non-adherence to prescribed asthma medications; dietary modifications unsuitable; current diagnosis of diabetes or active gastrointestinal disease; recent antibiotic or laxative use; nutritional, fibre or probiotic supplement use (this includes any vitamin or minerals, sports supplements, meal replacements, probiotics and fibre preparations) within the previous 4 weeks; current smokers; pregnancy or breastfeeding; chronic or excessive alcohol consumption; unexplained weight loss (>5% body weight) in the past 6 months; current use of anti-inflammatory medications (e.g. corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDS)); terminal illness; galactosemia or ragweed allergy.

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)
After eligibility is confirmed through a screening visit, subjects will be given a unique study number and randomisation number which will determine the order in which they receive the three study interventions.
Allocation will involve contacting the holder of the allocation schedule which is held by an independent statistician.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation sequence will be determined by an independent statistician using computer generated codes in a 4 by 4 latin square method.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Crossover
Other design features
Phase
Phase 2
Type of endpoint/s
Efficacy
Statistical methods / analysis
Within group comparisons of outcomes compared to baseline will be conducted using the student t-test or Wilcoxon signed-rank test. Per protocol analysis of mean difference in outcomes between groups will be tested using repeated-measurements ANOVA of period differences by treatment sequence. An independent ANOVA of period totals by treatment sequence will be used to test the assumption of no carry over effects. Associations between clinical outcomes, inflammatory biomarkers and plasma SCFA will be explored using Pearson or Spearman’s rank correlation coefficient.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
3/09/2018
Actual
14/09/2018
Date of last participant enrolment
Anticipated
29/07/2019
Actual
14/01/2020
Date of last data collection
Anticipated
18/11/2019
Actual
18/05/2020
Sample size
Target
32
Accrual to date
Final
40
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment hospital [1] 10356 0
Hunter Medical Research Institute - New Lambton Heights
Recruitment postcode(s) [1] 22027 0
2305 - New Lambton Heights

Funding & Sponsors
Funding source category [1] 298933 0
Commercial sector/Industry
Name [1] 298933 0
Australian Health and Nutrition Association Limited trading as Sanitarium Health & Wellbeing Company
Country [1] 298933 0
Australia
Primary sponsor type
University
Name
University of Newcastle
Address
University Drive,
Callaghan, NSW, 2308
Country
Australia
Secondary sponsor category [1] 298147 0
None
Name [1] 298147 0
Address [1] 298147 0
Country [1] 298147 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299869 0
Hunter New England Human Research Ethics Committee
Ethics committee address [1] 299869 0
Lookout Road
New Lambton NSW 2305
Postal address:
Locked Bag 1
Netw Lambton NSw 2305
Ethics committee country [1] 299869 0
Australia
Date submitted for ethics approval [1] 299869 0
27/04/2018
Approval date [1] 299869 0
02/08/2018
Ethics approval number [1] 299869 0

Summary
Brief summary
The purpose of this project is to investigate whether a soluble fibre supplement (an oligosaccharide blend) is effective in improving asthma control and reducing airway inflammation in adults with poorly controlled asthma. Soluble fibre comes from plant based foods (fruits, vegetables, grains) and is not digested until it reaches the bowel. When it reaches the bowel, the bacteria that live there break it down into small molecules, which are known to be beneficial for our immune system. In this study, we hope to gain further insight into the possible health benefits of soluble fibre in adults with poorly controlled asthma. The project involves a 16 week intervention where 32 participants with stable asthma will be allocated to take a high dose of soluble fibre (oligosaccharide blend) in one or two daily doses, a low dose of soluble fibre (oligosaccharide blend) and placebo control (maltodextrin) for 2 weeks, in random order, with a two week washout period between each supplement phase. Subjects will not know which supplement they are receiving throughout the study.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 81822 0
Prof Lisa Wood
Address 81822 0
School of Biomedical Science and Pharmacy
University of Newcastle
and
Hunter Medical Research Institute
Lot 1 Kookaburra Circuit
New Lambton Heights NSW 2305
Country 81822 0
Australia
Phone 81822 0
+61 2 49217 485
Fax 81822 0
+61 2 4042 0046
Email 81822 0
lisa.wood@newcastle.edu.au
Contact person for public queries
Name 81823 0
Dr Bronwyn Berthon
Address 81823 0
School of Biomedical Science and Pharmacy University of Newcastle and Hunter Medical Research Institute Lot 1 Kookaburra Circuit New Lambton Heights NSW 2305
Country 81823 0
Australia
Phone 81823 0
+61 2 4042 0116
Fax 81823 0
+61 2 4042 0046
Email 81823 0
bronwyn.berthon@newcastle.edu.au
Contact person for scientific queries
Name 81824 0
Prof Lisa Wood
Address 81824 0
School of Biomedical Science and Pharmacy
University of Newcastle
and
Hunter Medical Research Institute
Lot 1 Kookaburra Circuit
New Lambton Heights NSW 2305
Country 81824 0
Australia
Phone 81824 0
+61 2 49217485
Fax 81824 0
+61 2 4042 0046
Email 81824 0
lisa.wood@newcastle.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
3075Study protocol    Protocol will be published in the University of Ne... [More Details]



Results publications and other study-related documents

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