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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT06820281




Registration number
NCT06820281
Ethics application status
Date submitted
6/02/2025
Date registered
11/02/2025
Date last updated
11/02/2025

Titles & IDs
Public title
Acute Metabolic Effects of Tirzepatide in Type 1 Diabetes
Scientific title
Acute Metabolic Effects of Tirzepatide in Type 1 Diabetes: a Phase 2 Double Blinded Placebo Controlled Clinical Trial (TIRTLE2)
Secondary ID [1] 0 0
U1111-1316-2752
Universal Trial Number (UTN)
Trial acronym
TIRTLE2
Linked study record

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

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Treatment: Drugs - Tirzepatide 2.5mg weekly
Treatment: Drugs - Placebo injection (normal saline)

Experimental: Tirzepatide 2.5mg weekly - Administered subcutaneously.

Placebo comparator: Placebo - Administered subcutaneously.


Treatment: Drugs: Tirzepatide 2.5mg weekly
Tirzepatide 2.5 mg/0.5 mL solution for injection vial or pre-filled pen. Each vial/ pre-filled pen contains tirzepatide 2.5 mg in 0.5 mL solution (2.5mg in 0.6mL if Kwikpen)

Tirzepatide will be administered by drawing up into a syringe, then administering by subcutaneous injection weekly by study nurses.

Treatment: Drugs: Placebo injection (normal saline)
Placebo will be given as 0.5mL normal saline (if comparator against vial or pre-filled pen), or 0.6mL (if comparator against Mounjaro Kwikpen), drawn up into a syringe and administered by subcutaneous injection weekly by study nurses.
Intervention code [1] 0 0
Treatment: Drugs
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Whole-body insulin sensitivity
Timepoint [1] 0 0
4 weeks
Secondary outcome [1] 0 0
Adipose insulin sensitivity
Timepoint [1] 0 0
4 weeks
Secondary outcome [2] 0 0
Fasting glucagon
Timepoint [2] 0 0
4 weeks
Secondary outcome [3] 0 0
Prandial glucagon secretion
Timepoint [3] 0 0
4 weeks
Secondary outcome [4] 0 0
Glucagon response to hypoglycemia
Timepoint [4] 0 0
4 weeks
Secondary outcome [5] 0 0
Resting energy expenditure (REE)
Timepoint [5] 0 0
4 weeks
Secondary outcome [6] 0 0
Overnight growth hormone curve
Timepoint [6] 0 0
4 weeks
Secondary outcome [7] 0 0
Overnight free-fatty acids (FFA) curve
Timepoint [7] 0 0
4 weeks
Secondary outcome [8] 0 0
% fat mass
Timepoint [8] 0 0
4 weeks
Secondary outcome [9] 0 0
% fat free mass
Timepoint [9] 0 0
4 weeks
Secondary outcome [10] 0 0
Body weight
Timepoint [10] 0 0
4 weeks
Secondary outcome [11] 0 0
Total daily insulin dose
Timepoint [11] 0 0
4 weeks
Secondary outcome [12] 0 0
Total daily basal insulin dose
Timepoint [12] 0 0
4 weeks
Secondary outcome [13] 0 0
Total daily bolus insulin dose
Timepoint [13] 0 0
4 weeks
Secondary outcome [14] 0 0
% Time in Range (TIR)
Timepoint [14] 0 0
4 weeks
Secondary outcome [15] 0 0
% Time Below Range (TBR)
Timepoint [15] 0 0
4 weeks
Secondary outcome [16] 0 0
% Time level 1 hyperglycemia
Timepoint [16] 0 0
4 weeks
Secondary outcome [17] 0 0
% Time level 2 hyperglycemia
Timepoint [17] 0 0
4 weeks
Secondary outcome [18] 0 0
Glycemic variability
Timepoint [18] 0 0
4 weeks
Secondary outcome [19] 0 0
Arterial stiffness
Timepoint [19] 0 0
4 weeks

Eligibility
Key inclusion criteria
* age 18-55 years
* BMI = 27 kg/m2
* HbA1c = 9.0%
* insulin delivery using an automated insulin delivery system
* at least 2 years since diagnosis of type 1 diabetes
Minimum age
18 Years
Maximum age
55 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
* TZP or GLP-1 receptor agonist in last 3 months; metformin or sodium glucose co-transporter 2 (SGLT2) inhibitor in the last 6 weeks; steroids, antipsychotics, immunosuppressants in the last 6 weeks.
* Hypoglycemic unawareness or severe hypoglycemia last 6 months.
* History of seizure disorder.
* History of weight loss surgery.
* eGFR <60 mL/min/1.73 m2.
* Liver disease (known cirrhosis, LFTs > 3x upper limit of normal).
* Active malignancy.
* Pregnant, breastfeeding, planning pregnancy within 6 months, or not using adequate contraception.
* History of cardiovascular disease, or coronary event or stroke in last 3 months
* Hemoglobin level < 13.5 g/dL

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)
Methods used to generate the sequence in which subjects will be randomised (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
Parallel
Other design features
Phase
Phase 2
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
1/12/2025
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
31/12/2027
Actual
Sample size
Target
20
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment hospital [1] 0 0
Garvan Institute of Medical Research - Sydney
Recruitment postcode(s) [1] 0 0
2010 - Sydney

Funding & Sponsors
Primary sponsor type
Other
Name
Garvan Institute of Medical Research
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
This study will examine the effects of Tirzepatide (TZP), a glucagon-like peptide 1 (GLP1) - gastric inhibitory peptide (GIP) co-agonist, on metabolism in type 1 diabetes (T1D). Research participants with T1D will undergo measures of insulin sensitivity, and hormone levels post-meal, post-hypoglycemia and during the overnight period. These measures will be performed prior to, and after 4 weeks of treatment with TZP. These measures will also be compared to a group of adults without diabetes (who will not receive treatment with TZP) to assess how metabolism of energy and nutrients is different in T1D compared to people without diabetes.
Trial website
https://clinicaltrials.gov/study/NCT06820281
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Jennifer R Snaith, MD PHD
Address 0 0
Garvan Institute of Medical Research
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Jennifer R Snaith, MD PHD
Address 0 0
Country 0 0
Phone 0 0
+61 2 9298 8100
Fax 0 0
Email 0 0
[email protected]
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/study/NCT06820281