Did you know?

The ANZCTR now automatically displays published trial results and simplifies the addition of trial documents such as unpublished protocols and statistical analysis plans.

These enhancements will offer a more comprehensive view of trials, regardless of whether their results are positive, negative, or inconclusive.

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
ACTRN12620000936921
Ethics application status
Approved
Date submitted
3/06/2020
Date registered
21/09/2020
Date last updated
16/02/2022
Date data sharing statement initially provided
21/09/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
Optimising insulin doses for adolescents and adults with Type 1 diabetes using closed loop pumps.
Scientific title
Optimising postprandial glycaemia in adolescents and adults with Type 1 diabetes using Closed Loop Insulin Delivery.
Secondary ID [1] 301441 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 1 diabetes 317743 0
Condition category
Condition code
Metabolic and Endocrine 315812 315812 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study involves the provision of 2 different test meals in the form of pancakes of different ingredients, a high carbohydrate (HC) meal or high fat, high protein (HFHP) meal on 8 occasions over 2 consecutive weeks. Test meals will be observed under different insulin dosing conditions. The HC test meal will be observed under 4 conditions; 1) standard bolus given in manual mode 15 minutes prior to meal delivery, 2) standard bolus (100% insulin to carbohydrate ratio) given in manual mode 25 minutes prior to meal delivery, 3) standard bolus given in auto mode 15 minutes prior to meal delivery and 4) standard bolus given in auto mode 25 minutes prior to meal delivery. The HFHP test meal will also be observed under 4 conditions; 5) dual wave bolus (70:30, 3 h) in manual mode given 15 minutes prior to meal delivery, 6) dual wave bolus using 130% ICR (70:30, 3h) in manual mode, 7) standard bolus given in auto mode 10 minutes prior to meal delivery and 8) split bolus given in auto mode with bolus 1, equivalent to 100% of the individual ICR given 15 minutes prior to meal delivery and bolus 2, equivalent to 30% of the individual ICR given 60 minutes post- meal delivery.
Participants will be randomly allocated to receive both meal cohorts over the two weeks.
Standard bolus refers to 100% of the participants insulin to carbohydrate ratio for that meal..
High Carbohydrate Meal= 90g carbohydrate, less than 10g protein. less than 10g of fat
High Fat High Protein Meal= 30g carbohydrate, 50g of protein, 40g of fat
All meals will be provided and made to exact measurements. The pump records insulin dosages that we can review to ensure patient compliance.
Participants will have a face to face session at the Hunter Medical Research Institute where they will be provided with logbooks and all the meals prepared and frozen for them to take home and complete the study at home. A member of the study team will be in contact each day to ensure the study is going smoothly.
Intervention code [1] 317752 0
Treatment: Drugs
Comparator / control treatment
Individuals usual dose. 100% insulin to carbohydrate ratio
Control Conditions for High carbohydrate meal:
1. standard bolus (100% insulin to carbohydrate ratio) given in manual mode 15 minutes prior to meal
2. standard bolus (100% insulin to carbohydrate ratio) given in auto mode 15 minutes prior to meal
Control Conditions for High fat high protein meal:
1. standard bolus (100% insulin to carbohydrate ratio) given in auto mode as a dual wave bolus 15 minutes prior to meal
2. standard bolus (100% insulin to carbohydrate ratio) given in auto mode 15 minutes prior to meal
For both the HC and HFHP meal one day has been included that will give the participant 100% of their insulin to carbohydrate ratio. This will act as their own control for the study. Each participant will work as their own control a separate cohort will not be needed
Control group
Dose comparison

Outcomes
Primary outcome [1] 324019 0
Mean postprandial glucose excursion at 240 minutes from baseline for each condition after test meal consumption. This will be measured using a continuous glucose monitor.
Timepoint [1] 324019 0
Difference in mean glucose excursions at 240 mins post- meal. This will be measure in 30 minute intervals from baseline (0/meal consumption) until 240 minutes
Secondary outcome [1] 383555 0
Percent time in glucose target range (3.9-10 mmol/L)
Timepoint [1] 383555 0
Measured using continuous glucose monitor (cgm) from baseline (meal consumption) to 240mins

Eligibility
Key inclusion criteria
Diagnosed with type 1 diabetes >1 year
Using insulin pump therapy >6 months
Glycated haemoglobin less than or equal to 10.0%
Minimum age
12 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Co-existing major medical condition
Evidence of complications of diabetes

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 is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Differences in mean glucose excursions between insulin dosing conditions at each 30 min interval will be tested using generalised linear mixed models.

Recruitment
Recruitment status
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)
NSW
Recruitment hospital [1] 16831 0
John Hunter Children's Hospital - New Lambton
Recruitment hospital [2] 16832 0
John Hunter Hospital - New Lambton
Recruitment postcode(s) [1] 30473 0
2305 - New Lambton

Funding & Sponsors
Funding source category [1] 305877 0
Charities/Societies/Foundations
Name [1] 305877 0
Australasian Paediatric Endocrine Group
Country [1] 305877 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Australasian Paediatric Endocrine Group
Address
PO Box 180 Morisset NSW 2264
Country
Australia
Secondary sponsor category [1] 306328 0
None
Name [1] 306328 0
Address [1] 306328 0
Country [1] 306328 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 306137 0
Hunter New England Research Ethics Committee
Ethics committee address [1] 306137 0
Research Ethics and Governance Office Hunter New England Local Health District Locked Bag 1 New Lambton NSW 2305
Ethics committee country [1] 306137 0
Australia
Date submitted for ethics approval [1] 306137 0
Approval date [1] 306137 0
07/05/2020
Ethics approval number [1] 306137 0

Summary
Brief summary
This study is looking to find an optimal insulin-dosing strategy that effectively and safely controls blood glucose levels after meals in people with T1D on closed loop insulin pump therapy. The study involves 8 study days over the course of two weeks while the participant is using the currently available closed loop insulin pump system. The study will be split over two weeks with one week using the closed loop function and one week without. During this time the participant will test different insulin dosing strategies over two different meal types (4 meals will be high in carbohydrate, 4 meals will be high in fat and protein). Blood glucose will be measure through the cgm linked to the pump and this will be used to measure blood glucose levels and time in target after each meal. This will be used to determine the most effective insulin dosing strategy.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 102838 0
Dr Carmel Smart
Address 102838 0
John Hunter Children's Hospital, Dept of Paediatric Endocrinology, Lookout Rd New Lambton Heights, NSW, 2305
Country 102838 0
Australia
Phone 102838 0
+61 401624294
Fax 102838 0
Email 102838 0
Contact person for public queries
Name 102839 0
Jordan Rafferty
Address 102839 0
Hunter Medical Research Institute, Lot 1 Kookaburra Ct, New Lambton Heights, NSW, 2305
Country 102839 0
Australia
Phone 102839 0
+61 403106451
Fax 102839 0
Email 102839 0
Contact person for scientific queries
Name 102840 0
Jordan Rafferty
Address 102840 0
Hunter Medical Research Institute, Lot 1 Kookaburra Ct, New Lambton Heights, NSW, 2305
Country 102840 0
Australia
Phone 102840 0
+61 403106451
Fax 102840 0
Email 102840 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Ethics approval stipulates that data may only be presented/ shared as de- identified group data.


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.