COVID-19 studies are our top priority. For all other trials, there is a 4-week delay in processing a trial submitted/resubmitted to the ANZCTR and additional delays for updates of registered trials. We appreciate your patience.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
Protein digestibility of bread made from enzyme treated flour in adults with an ileostomy
Scientific title
Evaluation of the total protein and proline digestibility of bread made from enzyme treated flour in adults with an ileostomy
Secondary ID [1] 300404 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gut health 316037 0
Inadequate nutrition 316038 0
Condition category
Condition code
Oral and Gastrointestinal 314317 314317 0 0
Inflammatory bowel disease

Study type
Description of intervention(s) / exposure
The study is designed as a completely randomised, double-blinded, controlled cross-over intervention. A total of 4 proctocolectomised adults with conventional and well-functioning permanent ileostomies will be recruited. Eligibility will be confirmed by a screening questionnaire, followed by an in-home screen involving assessment of vital signs and self-reported medical history. The study will be conducted over 6 consecutive days within the participant’s home. This will comprise a 2-day acclimation period in which study participants will consume 5 slices of conventional bread. The participants will then be asked to consume 5 slices per day of either conventional bread or bread made using an enzyme blend, for a period of 2 days each (order to be randomly allocated) and collect ileostomy digesta from the ileostomy bag every 2 hours from 7am to 11pm and then again at 7am. A washout period is not required. The ileostomy digesta samples will be obtained from the participant’s home by research staff and analysed in the laboratory for total protein and amino acid content. Throughout the 6 days of the study, participants will consume a low protein (0.65-0.80g/kg BW/d) baseline diet (all foods will be provided) and asked to fill-out food checklists for assessment of compliance.
Intervention code [1] 316696 0
Comparator / control treatment
The control food will be bread made with conventional flour
Control group

Primary outcome [1] 322699 0
ileal protein digestibility (%) will be assessed by laboratory analysis of ileal digesta
Timepoint [1] 322699 0
48 hrs post commencement of consumption of each test bread
Primary outcome [2] 322700 0
ileal proline digestibility (%) will be assessed by laboratory analysis of ileal digesta
Timepoint [2] 322700 0
48 hrs post commencement of consumption of each test bread
Secondary outcome [1] 379345 0
Timepoint [1] 379345 0

Key inclusion criteria
• Adult male or female
• Aged 20-80 years inclusive.
• Health professional confirmation of minimal terminal ileum (up to 10 cm) removed more than 1 year ago and have a conventional and well-functioning permanent ileostomy deemed fit for the study intervention (confirmed by GP).
• Understand the study requirements, including digesta collections and willing to adhere closely to prescribed food consumption and alcohol restrictions as per the research protocol.
Minimum age
20 Years
Maximum age
80 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
• History of drug or alcohol abuse (i.e. > 14 serves alcohol/wk).*
• History of smoking within the 6 months prior to the study.
• Participation in a dietary intervention study within 30 days of commencement of this study.
• A current presence of having gastrointestinal, renal, hepatic disease, coeliac disease, irritable bowel disease or, inflammatory bowel disease including Crohn’s disease and ulcerative colitis*
• Use of any medication within the last 3 months that in the opinion of the investigator could interfere with the study or medications likely to modulate small intestinal function (See protocol for list of medications).
• Definite or suspected personal history or family history of adverse events or intolerance to bread or foods made from wheat.*
• Person considered by the investigator to be unwilling, unlikely or unable to comprehend or comply with the study protocol and restrictions.
• Unwilling or unable to collect ileal effluent as required.
* confirmed by trained Clinic Team Member; no clinical testing will be conducted to diagnose/confirm medical history.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
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
The people analysing the results/data
Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
In a study of similar design (Rowan et al, 1994), ileal protein digestibility was 86.9 (SD 2.17) % and proline digestibility was 89.9 (SD 2.95%). A study based on a complete set of data from 3 volunteers will provide sufficient power (80%) to detect a 10% improvement in ileal protein and proline absorption. Using these previously reported mean ileal protein digestibility and proline digestibility levels of 86.9 and 89.9%, respectively, a 10% change is expected to result in ileal protein digestibility levels of ~96.9% and proline digestibility of ~99.9%. Hence a change of 10% is a meaningful and realistic improvement to expect. To allow for one person dropping out from the study a total of 4 people will be recruited.
The effect of enzyme treatment of flour on the total protein and proline digestibility of bread will be determined by a two-tailed paired student t-test. These analyses will be performed using SPSS and criterion of significance will be p < 0.05.

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)

Funding & Sponsors
Funding source category [1] 304828 0
Commercial sector/Industry
Name [1] 304828 0
Address [1] 304828 0
1/115 Bluestone Cct
Seventeen Mile Rocks
QLD 4073
Country [1] 304828 0
Primary sponsor type
Government body
CSIRO Health and Biosecurity
Gate 13 Kintore Ave
Adelaide 5000
South Australia
Secondary sponsor category [1] 305159 0
Name [1] 305159 0
Address [1] 305159 0
Country [1] 305159 0

Ethics approval
Ethics application status
Ethics committee name [1] 305239 0
CSIRO Health and Medical Human Research Ethics Committee (CHM HREC)
Ethics committee address [1] 305239 0
Ecosciences Presinct, Dutton Park, QLD 4102
GPO Box 2583
Brisbane, QLD, 4001 Australia
Ethics committee country [1] 305239 0
Date submitted for ethics approval [1] 305239 0
Approval date [1] 305239 0
Ethics approval number [1] 305239 0
HREC 2019/093

Brief summary
It is suggested that incomplete digestion of proline-rich proteins, including gluten, may be a cause of food intolerance and food allergies in some people, and lead to gut discomfort and distress. Foods containing these proline-rich proteins are widespread in our diet and are present in a broad range of foods. To improve the digestibility of the protein in these foods, Biohawk has developed a unique enzyme blend that can be added during food manufacturing. Anecdotal evidence suggests that bread made with gluten-rich flour treated with this enzyme blend is well tolerated by people who report having sensitivity to wheat-based products. However, independent testing is needed to confirm this, and to determine whether total protein and proline digestibility is improved.
The main aim of this project is to evaluate the protein digestibility of bread products made from gluten-rich flour treated with an enzyme blend in healthy ileostomy participants.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 99726 0
Dr Damien Belobrajdic
Address 99726 0
Gate 13 Kintore Aevnue
Adelaide SA 5000
Country 99726 0
Phone 99726 0
+61 8 8303 8815
Fax 99726 0
Email 99726 0
Contact person for public queries
Name 99727 0
Dr Damien Belobrajdic
Address 99727 0
Gate 13 Kintore Aevnue
Adelaide SA 5000
Country 99727 0
Phone 99727 0
Fax 99727 0
Email 99727 0
Contact person for scientific queries
Name 99728 0
Dr Damien Belobrajdic
Address 99728 0
Gate 13 Kintore Aevnue
Adelaide SA 5000
Country 99728 0
Phone 99728 0
Fax 99728 0
Email 99728 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
To maintain commercial confidentiality and data privacy.
What supporting documents are/will be available?
No other documents available
Summary results
No Results