Tirzepatide for the Treatment of Concurrent Type 1 Diabetes and Overweight or Obesity

NCT06180616 | Not Yet Recruiting Phase 2 FDA Drug

• 1 other identifier: TZP-T1D
• Study Type: interventional
• Target: 40
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study is a 2-arm, double blinded, randomised clinical trial where 40 participants will be assigned 1:1 to insulin treatment alone (control) or insulin treatment and tirzepatide treatment for 32 weeks. The primary objective is to demonstrate that tirzepatide treatment, dose incremented to 15mg QW for 32 weeks adjunctive to insulin treatment can reduce body weight in patients with T1D and overweight or obesity when compared to insulin treatment alone. The secondary objective is to demonstrate that tirzepatide treatment, dose incremented to 15mg QW for 32 weeks can improve glycaemic control (measured by hbA1c), improve time in range, reduce insulin requirements, and reduce the severity of comorbidities in people with obesity and T1D. This trial includes a 6 month follow-up period.

Conditions

Type 1 Diabetes Mellitus; Overweight and Obesity

Keywords

Tirzepatide; GLP-1/GIP Agonist

Outcome Measures

Primary Outcomes (1)

• Body weight

  Percent body weight change (%)

  32 weeks

Secondary Outcomes (26)

• hbA1c

  32 weeks

• Time in range

  32 weeks

• Total daily insulin dose

  32 weeks

• Insulin carbohydrate ratio

  32 weeks

• Waist and neck circumference

  32 weeks

Study Arms (2)

Insulin Treatment

NO INTERVENTION

Participants will remain on their typical insulin therapy regime for 32 weeks

Tirzepatide Treatment

EXPERIMENTAL

Participants will remain on their typical insulin therapy regime and will also receive tirzepatide (dose incremented to 15mg QW) for 32 weeks.

Drug: Tirzepatide

Interventions

Tirzepatide DRUG

Tirzepatide will be self-administered subcutaneously by study participants via an injection. The drug will be taken weekly following the schedule: 4 weeks at 2.5 mg QW, 4 weeks at 5.0 mg QW, 4 weeks at 7.5 mg QW, 4 weeks at 10.0 mg QW, 4 weeks at 12.5 mg QW, 12 weeks at 15 mg QW. Modification of study drug will be performed if the participant is experiencing significant side effects and cannot tolerate the higher dosage of the study drug. In this instance, the study drug dosage will be reduced to the previously tolerated dosage and held at this dose for a further 4 weeks. One further attempt at dose escalation will be undertaken after 4 weeks, at the discretion of the participant and the study investigator. If recurrent side effects are experienced by the participant, the study drug will be returned to the previously tolerated dosage, and the prescription continued at this dosage for the remainder of the study.

Tirzepatide Treatment

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-70 years at screening
• A clinical diagnosis of T1D for at least 12 months at time of screening
• Body mass index ≥ 27kg/m2
• HbA1c ≤ 10%
• Capable and willing to self-inject tirzepatide once per week
• In women of childbearing potential, a negative pregnancy test and willing to use effective contraception consistently for the duration of the study
• Able and willing to provide written informed consent for study participation
• Able and willing to use Easy Diet Diary
• Able and willing to keep an exercise log
• Willing to share devices data uploads
• Has current glucagon product to treat severe hypoglycaemia
• Has current ketone meters to check ketones

You may not qualify if:

• Age \<18 years and \>70 years
• A clinical diagnosis of diabetes type other than T1D
• HbA1c \> 10%
• Use of GLP-1 receptor agonist within 1 month of study screening
• Use of any glucose lowering medications aside from insulin within 1 month of study screening
• History of hypersensitivity to investigational medicinal product or related product
• Obesity that is induced by other endocrine disorders
• Pregnancy or positive pregnancy test at time of screening, or unwilling to use effective contraception consistently for the duration of the study which is defined in Appendix 1
• Active proliferative diabetic retinopathy, maculopathy, or severe no proliferative diabetic retinopathy requiring acute treatment
• Known gastric emptying abnormality
• History of chronic or acute pancreatitis, uncontrolled hypertension, acute cardiovascular condition within 3 months
• No longer than 12 months of insulin treatment
• Not willing to use a NovoPen 6 to record insulin dosing if currently using multiple daily injections
• Insulin pump, CGM or smart phone devices are not compatible for data transfer
• Not willing to share device data

Sponsors & Collaborators

• Royal North Shore Hospital: lead

Related Publications (1)

• Purcell AR, Rodrigo N, Longfield MSG, Glastras SJ. Tirzepatide for the treatment of adults living with concurrent type 1 diabetes and overweight or obesity (TZP-T1D): a double-blind, placebo-matched randomised controlled trial protocol. BMJ Open. 2025 Sep 16;15(9):e093775. doi: 10.1136/bmjopen-2024-093775.

  PMID: 40962353 DERIVED

MeSH Terms

Conditions

Diabetes Mellitus, Type 1; Overweight; Obesity

Interventions

Tirzepatide

Condition Hierarchy (Ancestors)

Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Autoimmune Diseases; Immune System Diseases; Overnutrition; Nutrition Disorders; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptide Receptors; Receptors, G-Protein-Coupled; Receptors, Cell Surface; Membrane Proteins; Proteins; Amino Acids, Peptides, and Proteins; Receptors, Gastrointestinal Hormone; Receptors, Peptide

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: November 21, 2023
• First Posted: December 22, 2023
• Study Start (Estimated): December 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028
• Last Updated: July 29, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, CSR