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Trial registered on ANZCTR

Registration number
Ethics application status
Not yet submitted
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Testing efficacy of Breath Pearls for management of bad breath associated with a very low calorie diet (VLCD)
Scientific title
Can compliance with VLCD be improved using Breath Pearls to manage halitosis: a prospective double blinded randomised controlled trial
Secondary ID [1] 301120 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Halitosis 317213 0
Condition category
Condition code
Oral and Gastrointestinal 315354 315354 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Study type
Description of intervention(s) / exposure
The intervention will begin in the second week of the VLCD, either soft-gel capsules of peppermint oil (Breath Pearls™) or placebo. Two capsules will be taken orally three times a day (after meals). The placebo and active treatments will be identical in packaging and delivery.
Bottle of Breath Pearls/placebo will be collected by the study nurse on the morning of surgery to assess compliance for counting of the remaining capsules
Intervention code [1] 317429 0
Treatment: Other
Comparator / control treatment
The placebo treatment is composed of sunflower oil
Control group

Primary outcome [1] 323612 0
Change in halitosis rating as assessed by change in HALT questionnaire score
Timepoint [1] 323612 0
2 weeks after commencement of Very low calorie diet
Secondary outcome [1] 382349 0
Any change in gastro intestinal quality of life questionnaire score
Timepoint [1] 382349 0
The gastro intestinal quality of life questionnaire will be administered at the commencement of VLCD (0) time point, the end of week 1 and the end of week 2
Secondary outcome [2] 382350 0
Compliance with VLCD assessed by measuring urine ketones the morning of surgery
Timepoint [2] 382350 0
2 weeks after the commencment of VLCD,
Secondary outcome [3] 382351 0
Measuring weight change from the commencement of VLCD to weight following 2 weeks of VLCD. Weight will be measured using the same digital weighing scales
Timepoint [3] 382351 0
2 weeks post commencement of VLCD

Key inclusion criteria
Patients will be considered for inclusion if they are planned for bariatric surgery and on a VLCD.
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
• will not accept the randomisation process;
• have medical issues which contraindicate the application of either arm of the study such as acute myocardial infarction within the past 6 months, dementia, bulimia, active psychosis, concurrent experimental drug use, current pregnancy, lactation, illicit drug use, excessive alcohol intake, use of drugs known to affect body composition, cytotoxic drugs, internal malignancy, or major organ failure;
• are unable to understand the risks, realistic benefits and compliance requirements of the interventions.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
The random assignment of eligible patients will be computer generated by the Monash University School of Public Health and Preventative Medicine (SPHPM) data centre which employs this type of system for all major trials.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A telephone based system will be established which will allow a check of patent eligibility and randomisation only proceed if the patient meets the criteria. Randomisation will be clustered into blocks of between 6 and 8 to ensure even distribution.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
. For the primary endpoint, a 95% CI for the difference in proportions between groups will be inspected and equivalence will be declared if the ends of the CI both fall within the equivalence margin (-5%, +5%). If necessary, a secondary set of analyses will be performed to adjust for baseline characteristics that are found to be imbalanced between groups where imbalance is pre-specified as a 0.25 standard deviation difference in means (quantitative measures) or an odds ratio of 1.5 (binary measures). Multivariate analysis will be performed using multiple logistic regression for binomial outcomes adjusting for baseline imbalances and potential covariates. Data analysis will be completed by an independent statistician who will be blinded to the allocation of groups. We will analyze by Intent to Treat, Last Observation Carried Forwards (ITT LOCF), Observed case and by Completer analysis, to give estimates of the effect size based on each of these scenarios.

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 30119 0
3144 - Malvern
Recruitment postcode(s) [2] 30120 0
3181 - Windsor

Funding & Sponsors
Funding source category [1] 305563 0
Commercial sector/Industry
Name [1] 305563 0
Myerton Australia PTY LTD
Address [1] 305563 0
Suite 309, 1 Princess Street, Kew Victoria 3101
Country [1] 305563 0
Primary sponsor type
Monash University
Professor Wendy Brown
Department of Surgery
The Alfred Centre
99 Commercial Rd
Melbourne 3004 Victoria
Secondary sponsor category [1] 305970 0
Name [1] 305970 0
Address [1] 305970 0
Country [1] 305970 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 305869 0
Ramsay Health Research Governance Committeee
Ethics committee address [1] 305869 0
Level 3, 5 Talavera Road
Macquarie Park NSW 2113
Ethics committee country [1] 305869 0
Date submitted for ethics approval [1] 305869 0
Approval date [1] 305869 0
Ethics approval number [1] 305869 0

Brief summary
Patients who are planned to undergo bariatric surgery will typically undertake a Very Low Calorie Diet (VLCD) for two weeks prior to surgery to reduce the size of the liver and improve intraoperative laparoscopic access. VLCD are effective as they create a state of Ketosis. Ketosis leads to an unpleasant taste in the mouth and patients often struggle with this symptom whilst they are on the diet and can be one reason that they are not compliant with the treatment. We have chosen this group to study rather than our gastroparesis and post-surgical patients as there are currently no other effective treatments that can be offered.
We propose a double blinded randomised controlled trial to test the effectiveness of enterically delivered peppermint oil (Breath Pearls™) to improve the perception of breath quality for patients who are on a VLCD. If this trial confirms that patients have the perception of improved breath quality, we will plan to further investigate the mechanism by which this occurs and also extend the study to other cohorts that may benefit from this treatment.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 101874 0
Mr Paul Burton
Address 101874 0
Department of Surgery
Level 6 The Alfred Centre
99 Commercial Rd
Melbourne 3004 Victoria
Country 101874 0
Phone 101874 0
+61 3 99030190
Fax 101874 0
+61 3 99030717
Email 101874 0
Contact person for public queries
Name 101875 0
Mr Paul Burton
Address 101875 0
Department of Surgery
Level 6 The Alfred Centre
99 Commercial Rd
Melbourne 3004 Victoria
Country 101875 0
Phone 101875 0
+61 3 99030190
Fax 101875 0
+61 3 99030717
Email 101875 0
Contact person for scientific queries
Name 101876 0
Mr Paul Burton
Address 101876 0
Department of Surgery
Level 6 The Alfred Centre
99 Commercial Rd
Melbourne 3004 Victoria
Country 101876 0
Phone 101876 0
+61 3 99030190
Fax 101876 0
+61 3 99030717
Email 101876 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
What data in particular will be shared?
Deidentified data including weight , Questionnaire scores, and level of compliance using urine ketosis measurements
When will data be available (start and end dates)?
Staring immediately following publication with no end date
Available to whom?
Anyone who wishes to access it
Available for what types of analyses?
Any purpose
How or where can data be obtained?
Data can be obtained by emailing the principal investigator,
What supporting documents are/will be available?
Study protocol
Statistical analysis plan
Informed consent form
Clinical study report
Ethical approval
How or where can supporting documents be obtained?
Type [1] 7766 0
Study protocol
Citation [1] 7766 0
Link [1] 7766 0
Email [1] 7766 0
Other [1] 7766 0
Attachment [1] 7766 0
Type [2] 7767 0
Statistical analysis plan
Citation [2] 7767 0
Link [2] 7767 0
Email [2] 7767 0
Other [2] 7767 0
Attachment [2] 7767 0
Type [3] 7768 0
Informed consent form
Citation [3] 7768 0
Link [3] 7768 0
Email [3] 7768 0
Other [3] 7768 0
Attachment [3] 7768 0
Type [4] 7769 0
Clinical study report
Citation [4] 7769 0
Link [4] 7769 0
Email [4] 7769 0
Other [4] 7769 0
Attachment [4] 7769 0
Type [5] 7770 0
Ethical approval
Citation [5] 7770 0
Link [5] 7770 0
Email [5] 7770 0
Other [5] 7770 0
Attachment [5] 7770 0
Summary results
No Results