A Clinical Trial Using Tirzepatide to Help Adults With Type 1 Diabetes Automatically Control Their Blood Sugar (TZP)

Fully Closed-Loop Glucose Control in Adults With Type 1 Diabetes Using Tirzepatide: a Randomized, Multi-center, Open-label, Non-inferiority, Parallel Trial

This research study is testing whether a weekly medication called tirzepatide can help adults with type 1 diabetes use their insulin pump more easily, specifically by reducing or eliminating the need to count carbohydrates at meals.

People with type 1 diabetes must take insulin for life, and even with advanced insulin pumps and continuous glucose monitors, many still struggle to keep blood sugar within the target range. One of the biggest challenges is carbohydrate counting, which requires estimating the amount of carbohydrates in every meal to give the correct insulin dose.

Tirzepatide is a medication currently approved for type 2 diabetes and weight management. Early research suggests it may also help people with type 1 diabetes by lowering appetite, slowing digestion, reducing insulin needs, and smoothing after-meal blood sugar rises.

This study will include 105 adults with type 1 diabetes at centers in Canada and Switzerland. Everyone will use the Tandem Control-IQ insulin pump with a Dexcom G7 continuous glucose monitor. Participants are randomly assigned to one of two groups:

Tirzepatide group:

Participants receive weekly tirzepatide injections. After the dose is gradually increased over 12 weeks, they will eventually try using their insulin pump without entering carbohydrate amounts at meals.

Control group:

Participants continue their usual therapy and keep counting carbohydrates for their mealtime insulin doses.

The main goal of the study is to learn whether people taking tirzepatide can safely maintain good blood sugar control without counting carbs, compared with standard care. All participants will attend several clinic visits and share their glucose, insulin, and health data throughout the 32-week trial. Some centers will also conduct heart/fitness, or body-composition tests.

As with any medication, tirzepatide may cause side effects such as nausea, vomiting, diarrhea, or decreased appetite. Rare but serious risks like gallbladder disease or pancreatitis are also monitored. Pregnancy must be avoided during the trial.

Overall, this study aims to understand whether adding tirzepatide to automated insulin delivery can simplify diabetes management, reduce burden, and maintain safe and effective glucose control for adults living with type 1 diabetes.

Study Overview

• Status: Recruiting
• Conditions: Type 1 Diabetes; Type 1 Diabetes Mellitus; T1DM; T1D; T1DM - Type 1 Diabetes Mellitus
• Intervention / Treatment: Drug: Tirzepatide; Device: Tandem Control-IQ Automated Insulin Delivery System (with Dexcom G7 CGM); Behavioral: Carbohydrate Counting; Behavioral: No Meal Announcement

Detailed Description

Current diabetes technology, including hybrid automated insulin delivery systems like the Tandem Control-IQ paired with the Dexcom G7 continuous glucose monitor, improves glucose control but still relies heavily on patients entering carbohydrate amounts before eating, a task that is difficult, error-prone, and often stressful.

Tirzepatide, which is approved for type 2 diabetes and weight management, works by slowing digestion, lowering appetite, reducing insulin requirements, and improving after-meal glucose spikes, and early evidence suggests it may offer similar benefits in type 1 diabetes. This study is designed to determine whether adding once-weekly tirzepatide injections to a commercially available automated insulin delivery system can make diabetes management easier for adults with type 1, particularly by reducing or eliminating the need to count carbohydrates at meals.

In this 32-week trial, 105 adults will be randomly assigned to receive tirzepatide or no tirzepatide while all participants use the Control-IQ system. Those receiving tirzepatide will gradually increase their dose over 12 weeks, continue counting carbohydrates until week 26, and then stop announcing meals entirely for the final 6 weeks, while the control group will count carbohydrates throughout.

Across the study, participants will attend scheduled clinic visits, complete remote follow-ups, undergo laboratory tests, and, depending on the site, may complete heart function tests, body-composition scans, fitness testing, or gastric emptying assessments. Researchers will compare glucose control, insulin needs, weight, metabolic markers, meal patterns, and patient-reported outcomes between groups, with the primary goal of determining whether glucose management without carbohydrate counting is not worse than (non-inferior to) standard carbohydrate counting.

The study also closely monitors safety, as tirzepatide can cause nausea, vomiting, diarrhea, decreased appetite, and rare complications such as gallbladder disease or pancreatitis. Overall, this research aims to learn whether combining tirzepatide with automated insulin delivery can safely simplify diabetes management, reduce treatment burden, and improve metabolic outcomes for adults living with type 1 diabetes.

• Study Type: Interventional
• Enrollment (Estimated): 105
• Phase: Phase 2; Phase 3

Contacts and Locations

• Study Contact: Name: Keddy Moise, MSc (candidate); Phone Number: 438-531-6896; Email: keddy.moise@mail.mcgill.ca
• Study Contact Backup: Name: Rebecca Boyer-Hernandez, BSc; Email: rebecca.boyer-hernandez@affiliate.mcgill.ca

Study Locations

• Canada
  • Quebec
    • Montreal, Quebec, Canada, H4A 3J1
      • Not yet recruiting
      • McGill University Health Centre
      • Sub-Investigator: Abhinav Sharma, MD
      • Sub-Investigator: Ahmad Haidar, PhD
      • Sub-Investigator: Natasha Garfield, MD
      • Sub-Investigator: Michael A Tsoukas, MD
      • Contact: Keddy Moise, MSc (candidate); Phone Number: 438-531-6896; Email: keddy.moise@mail.mcgill.ca
      • Contact: Rebecca Boyer-Hernandez, BSc.; Phone Number: 514-318-7298; Email: rebecca.boyer-hernandez@affiliate.mcgill.ca
      • Principal Investigator: Melissa-Rosina Pasqua, MD, PhD
    • Montreal, Quebec, Canada, H2W 1R7
      • Not yet recruiting
      • Institut de recherches cliniques de Montreal
      • Contact: Rémi Rabasa-Lhoret, MD-PhD; Phone Number: 514-987-5762; Email: remi.rabasa-lhoret@umontreal.ca
      • Sub-Investigator: Rémi Rabasa-Lhoret, MD-PhD
    • Montreal, Quebec, Canada, H4A 3T2
      • Recruiting
      • Hygea Medical Clinic
      • Contact: Keddy Moise, MSc (candidate); Phone Number: 438-531-6896; Email: keddy.moise@mail.mcgill.ca
      • Contact: Rebecca Boyer-Hernandez, BSc; Email: rebecca.boyer-hernandez@affiliate.mcgill.ca
      • Principal Investigator: Melissa-Rosina Pasqua, MD, PhD
      • Sub-Investigator: Michael Tsoukas, MD
• Switzerland
  • Bern, Switzerland, 3010
    • Not yet recruiting
    • Insel Hospital, University Hospital Bern
    • Contact: Tabea Schoenfeldt-Reichmann, PhD; Phone Number: +41 31 664 34 17; Email: evatabea.schoenfeldt-reichmann@extern.insel.ch
    • Sub-Investigator: Lia Bally, MD-PhD
    • Sub-Investigator: Christoph Grani, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥ 18 years.
• Clinical diagnosis of type 1 diabetes for ≥ 1 year, per investigator judgment (confirmatory C-peptide and autoantibodies not required).
• A BMI ≥ 27 kg/m2.
• HbA1c > 6.5%, and < 12%.
• Current therapy: multiple daily injections or insulin pump.
• Willingness to use Tandem Control IQ insulin pump system with the use of rapid or ultra rapid-acting insulins compatible with Tandem Control-IQ pump (e.g. Fiasp is not compatible)
• Active carbohydrate counting for prandial insulin dosing.
• Individuals of childbearing potential must be using or agree to use an effective birth-control method. Childbearing potential refers to participants of the female sex post-menarche who have not reached menopause and who do not have a medical condition causing sterility (e.g., hysterectomy). Post-menopausal state refers to the absence of menses for 12 months without any alternative cause.

Exclusion Criteria:

• Use of GLP1-RAs within the last four weeks.
• Use of antihyperglycemic agents other than insulin or metformin within the last 2 weeks.
• Planned or ongoing pregnancy.
• Breastfeeding.
• Severe hypoglycemia requiring hospitalization in the past 2 months. Severe hypoglycemia is defined as requiring the assistance of another person, due to altered consciousness, to administer carbohydrates, glucagon, or other resuscitative actions.
• Diabetic ketoacidosis within the last 2 months.
• History of acute or chronic pancreatitis.
• Personal or family history of medullary thyroid cancer or multiple endocrine neoplasia type 2.
• Severe renal impairment with eGFR <30 mL/min/1.73 m2 (CKD-EPI), measured within the last four months.
• Clinically significant proliferative diabetic retinopathy or gastroparesis, as per the judgment of the investigator.
• Current or ≤ 1 month use of supraphysiological doses of oral or intravenous glucocorticoids.
• History of bariatric surgery within the last 6 months.
• Medical or psychiatric illness likely to interfere with participation (e.g. cirrhosis, active cancer, decompensated schizophrenia), per investigator judgment.
• Inability or unwillingness to comply with safe diabetes management practices, in the view of the investigator.
• Any safety concern that, in the investigator's judgment, precludes participation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tirzepatide group; Participants randomized to this arm receive once-weekly subcutaneous tirzepatide in addition to use of the Tandem Control-IQ insulin pump and Dexcom G7 continuous glucose monitor. Tirzepatide is initiated at 2.5 mg weekly and increased by 2.5 mg every 4 weeks to a target dose of 10 mg weekly or the maximally tolerated dose. Dose escalation may be delayed or reduced if participants experience intolerable gastrointestinal symptoms. During Weeks 1-26, participants continue standard carbohydrate counting for all meals. Beginning in Week 27, participants stop entering carbohydrate amounts into the pump (no meal announcements) for six weeks while continuing tirzepatide at their maintenance dose. Throughout the intervention, participants undergo regular safety assessments, remote glucose data reviews, insulin-pump parameter adjustments as needed, and scheduled in-person visits to monitor metabolic, cardiovascular, and patient-reported outcomes.	Drug: Tirzepatide; Tirzepatide, administered as a once-weekly subcutaneous injection, initiated at 2.5 mg and escalated in 2.5-mg increments every 4 weeks to a target of 10 mg or the maximally tolerated dose, used as an adjunct therapy in adults with type 1 diabetes using the Tandem Control-IQ automated insulin delivery system.; Other Names: Mounjaro; Device: Tandem Control-IQ Automated Insulin Delivery System (with Dexcom G7 CGM); This intervention uses the Tandem t:slim X2 insulin pump with the Control-IQ automated insulin delivery algorithm, integrated with the Dexcom G7 continuous glucose monitor. The system adjusts basal insulin and delivers automated correction boluses based on real-time glucose values. All participants receive standardized training and use this system for the full 32-week study. Rapid-acting insulin compatible with Control-IQ is required. This intervention is distinguished by its use under two different operational strategies: standard carbohydrate counting in the control arm and complete omission of meal announcements during the final 6 weeks in the tirzepatide arm.; Other Names: Dexcom G7; Control-IQ; Behavioral: Carbohydrate Counting; Participants enter the estimated carbohydrate amount for every meal and snack into the Tandem Control-IQ insulin pump to calculate and deliver prandial insulin boluses. This reflects standard use of hybrid closed-loop systems. The procedure is maintained for the entire 32-week study in the control arm and during Weeks 1-26 in the tirzepatide arm.; Other Names: Meal Announcement; Behavioral: No Meal Announcement; Participants do not enter carbohydrate amounts or announce meals to the Tandem Control-IQ system. The pump operates without user-initiated prandial boluses, relying solely on automated basal adjustments and automated correction boluses. This intervention is implemented only in the tirzepatide arm during Weeks 27-32.; Other Names: Omission of Carbohydrate Counting
Active Comparator: Control group; Participants randomized to the control arm use the Tandem Control-IQ automated insulin delivery system with the Dexcom G7 continuous glucose monitor, following standard-of-care diabetes management. They continue carbohydrate counting for all meals throughout the 32-week study and deliver prandial insulin boluses based on estimated carbohydrate intake, as is typical for users of hybrid closed-loop systems. No tirzepatide injections are administered. Participants receive the same device training, follow-up schedule, safety monitoring, glucose data reviews, and pump parameter adjustments as the tirzepatide arm. This arm serves as an active comparator, representing current standard therapy for type 1 diabetes with automated insulin delivery and meal announcements.	Device: Tandem Control-IQ Automated Insulin Delivery System (with Dexcom G7 CGM); This intervention uses the Tandem t:slim X2 insulin pump with the Control-IQ automated insulin delivery algorithm, integrated with the Dexcom G7 continuous glucose monitor. The system adjusts basal insulin and delivers automated correction boluses based on real-time glucose values. All participants receive standardized training and use this system for the full 32-week study. Rapid-acting insulin compatible with Control-IQ is required. This intervention is distinguished by its use under two different operational strategies: standard carbohydrate counting in the control arm and complete omission of meal announcements during the final 6 weeks in the tirzepatide arm.; Other Names: Dexcom G7; Control-IQ; Behavioral: Carbohydrate Counting; Participants enter the estimated carbohydrate amount for every meal and snack into the Tandem Control-IQ insulin pump to calculate and deliver prandial insulin boluses. This reflects standard use of hybrid closed-loop systems. The procedure is maintained for the entire 32-week study in the control arm and during Weeks 1-26 in the tirzepatide arm.; Other Names: Meal Announcement

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Daytime Time-in-Range	The primary outcome is the percentage of daytime hours (06:00-24:00) during which participants' glucose levels, measured by the Dexcom G7 continuous glucose monitor, fall within the target range of 3.9-10.0 mmol/L.	During the final 6 weeks of the study

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight	Change in body weight to assess the effects of tirzepatide on body composition. Weight is measured in kilograms.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study
Height	Change in height to assess the effects of tirzepatide on body composition. Height is measured in meters.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study.
Body Mass Index	Change in BMI to assess the effects of tirzepatide on body composition. BMI is measured in kilograms per square meter.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study
Waist circumference	Change in waist circumference to assess the effects of tirzepatide on body composition. Waist circumference is measured in centimetres.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study
Waist-to-Hip Ratio	Change in waist-to-hip ratio to assess the effects of tirzepatide on body composition. Waist-to-Hip Ratio is measured by dividing the waist circumference by the hip circumference. It is unitless.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study.
Systolic Blood Pressure	Change in systolic blood pressure to evaluate the cardiovascular effects of tirzepatide. Systolic blood pressure is measured in millimetres of mercury.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study.
Diastolic Blood Pressure	Change in diastolic blood pressure to evaluate the cardiovascular effects of tirzepatide. Diastolic blood pressure is measured in millimetres of mercury.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study.
Resting Heart Rate	Change in resting heart rate to assess the cardiovascular effects of tirzepatide. Resting heart rate is measured in beats per minute.	At enrollment, Week 8, Week 16, Week 24, and Week 32, At Week 8 and Week 16 post-study.
Insulin-related measures	Daily insulin requirements, including basal insulin, bolus insulin, and total insulin units per day, recorded through the insulin pump. Total insulin use normalized to body weight (units/kg/day) to assess treatment-related changes in insulin sensitivity. Carbohydrate amounts entered for bolus dosing (control arm and Weeks 1-26 of tirzepatide arm).	Continuously from randomization through Week 32, with primary analysis focused on Weeks 27-32, At Week 8 and Week 16 post-study.
Glucose outcomes	Percentage of CGM readings within 3.9-10.0 mmol/L, 3.9-7.8 mmol/L, <3.9 mmol/L, <3.0 mmol/L, >10.0 mmol/L, and >13.9 mmol/L, as well as mean glucose, glucose standard deviation, and glucose coefficient of variation.	Continuously collected from randomization through Week 32, with key comparisons during Weeks 23-26 and Weeks 27-32, At Week 8 and Week 16 post-study.
Glycated Hemoglobin (HbA1c)	Change in glycated hemoglobin (HbA1c) to assess overall glycemic control over the study period.	At enrollment, mid-study at Week 16, and at the end-of-study visit at Week 32, At Week 8 and Week 16 post-study.
Estimated Glomerular Filtration Rate	Changes in estimated glomerular filtration rate. eGFR is measured in millilitres/minute/body surface.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Serum Creatinine	Changes in serum creatinine. Serum creatinine is measured in umol/L.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Albumin-to-Creatinine Ratio	Changes in urinary albumin-to-creatinine ratio. Urinary albumin-to-creatinine ratio is measured in mg/mmol.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Lipid Panel (Total Cholesterol, LDL-C, HDL-C, Triglycerides)	Changes in fasting lipid profile to assess cardiometabolic effects of tirzepatide. All components of the lipid panel are measured in millimole/liter.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Liver Function Markers (Alanine transaminase, Alkaline phosphatase)	Changes in liver enzymes to monitor hepatic safety. Hepatic enzymes are measured in Units per Litre.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Liver Function Markers (Bilirubin)	Changes in bilirubin to monitor hepatic safety. Bilirubin (Total, Direct, Indirect) are measured in micromoles per litre.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Cardiac Biomarkers (NT-proBNP)	Serum biomarker used to assess cardiac strain, providing insights into the broader metabolic effects of tirzepatide. NT-proBNP is measured in picograms per millilitre.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Inflammatory Biomarkers (hs-CRP)	Serum biomarkers used to assess inflammation providing insights into the broader metabolic effects of tirzepatide. hs-CRP is measured in milligrams per litre.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
Inflammatory Biomarkers (IL-6)	Serum biomarkers used to assess inflammation, providing insights into the broader metabolic effects of tirzepatide. IL-6 is measured in picograms per millilitre.	At enrollment, Week 16, and Week 32, At Week 8 and Week 16 post-study.
C-Peptide	Change in fasting C-peptide to assess residual β-cell function.	At enrollment and at Week 32, At Week 8 and Week 16 post-study.
Carotid-Femoral Pulse Wave Velocity and Pulse Wave Analysis	Measures of arterial stiffness and central blood pressure, used to evaluate vascular effects of treatment.	At enrollment and at Week 32 (site-dependent).
DXA Body Composition	Whole-body DXA assessment of fat mass, lean mass, visceral fat, and bone density.	At enrollment and at Week 32 (site-dependent).
Echocardiogram (Diastolic Function Parameters)	Assessment of cardiac structure and diastolic function, including E/A ratio, e', E/e', and left atrial volume.	At enrollment and at Week 32 (site-dependent).
VO₂-max Test	Measurement of maximal oxygen consumption to evaluate cardiopulmonary fitness.	At enrollment and at Week 32 (site-dependent).
Quality-of-Life Measures (Diabetes Distress Scale)	Changes in the standardized Diabetes Distress Scale using the validated questionnaire. A participant's score is measured as the sum of responses to the appropriate items divided by the number of items in that scale. A mean item score 2.0 - 2.9 is considered moderate distress, and a mean item score > 3.0 is considered high distress.	At enrollment and at Week 32.
Quality-of-Life Measures (Hypoglycemia Fear Survey II)	Changes in the standardized Hypoglycemia Fear Survey II using the validated questionnaire. HFS-II Total Score range: 0-132. Higher scores on the total HFS-II indicate a greater fear of hypoglycemia. The questionnaire does not have pre-defined cut-off scores for diagnostic categories; instead, the scores are used to measure the level of fear.	At enrollment and at Week 32.
Quality-of-Life Measures (Three Factor Eating r18 Questionnaire)	Changes in the standardized Three Factor Eating Questionnaire scores. The three-factor eating questionnaire provides a score from 0 to 100 for cognitive restraint, uncontrolled eating, and emotional eating. Higher scores indicate greater cognitive restraint, uncontrolled eating, and emotional eating.	At enrollment and at Week 32.
Gastric Emptying via [13C] Acetate Breath Test	Rate of gastric emptying assessed by breath ¹³CO₂ appearance following standardized test meal.	At enrollment (or training visit) and at Week 32 (site-dependent).
Blood Glucagon Response to Standardized Meal	Change in glucagon concentrations following ingestion of a standardized liquid meal.	At enrollment and at Week 32 (site-dependent).
Meal Tracking Using Keenoa or MyFood24	Assessment of caloric intake and macronutrient composition via 3-day dietary records.	Prior to randomization, during Week 16, and during Week 32.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Severe hypoglycemia	Episode requiring the assistance of another person, due to altered consciousness, to administer carbohydrates, glucagon, or other resuscitative actions.	From the time the participant signs informed consent until the end of study participation at Week 32, with additional safety follow-up at Week 8 and Week 16 post-study.
Diabetic Ketoacidosis	Clinical episode characterized by hyperglycemia/euglycemia, ketonemia or ketonuria, metabolic acidosis, and associated symptoms such as nausea, vomiting, abdominal pain, rapid breathing, or altered consciousness. Events requiring emergency evaluation, intravenous fluids, or hospital treatment will be recorded as DKA. All episodes will be assessed for severity, timing, precipitating factors, and their relationship to study interventions, including tirzepatide use and automated insulin delivery performance.	From the time the participant signs informed consent until the end of study participation at Week 32, with additional safety follow-up at Week 8 and Week 16 post-study.
Gastrointestinal and related side effects	Nausea Vomiting Abdominal pain Diarrhea Constipation Liver profile changes Gallbladder disease Acute pancreatitis Other related side effects	From the time the participant signs informed consent until the end of study participation at Week 32, with additional safety follow-up at Week 8 and Week 16 post-study.

Collaborators and Investigators

• Sponsor: McGill University Health Centre/Research Institute of the McGill University Health Centre
• Collaborators: Institut de Recherches Cliniques de Montreal; Insel Gruppe AG, University Hospital Bern; Breakthrough T1D
• Investigators: Study Director: Ahmad Haidar, PhD, McGill University Health Centre/Research Institute of the McGill University Health Centre; Principal Investigator: Melissa-Rosina Pasqua, MD, PhD, McGill University Health Centre/Research Institute of the McGill University Health Centre

Publications and helpful links

General Publications

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• Peacock S, Frizelle I, Hussain S. A Systematic Review of Commercial Hybrid Closed-Loop Automated Insulin Delivery Systems. Diabetes Ther. 2023 May;14(5):839-855. doi: 10.1007/s13300-023-01394-5. Epub 2023 Apr 5.
• Janez A, Guja C, Mitrakou A, Lalic N, Tankova T, Czupryniak L, Tabak AG, Prazny M, Martinka E, Smircic-Duvnjak L. Insulin Therapy in Adults with Type 1 Diabetes Mellitus: a Narrative Review. Diabetes Ther. 2020 Feb;11(2):387-409. doi: 10.1007/s13300-019-00743-7. Epub 2020 Jan 4.

Helpful Links

• Mounjaro Monograph

Study record dates

Study Major Dates

• Study Start (Actual): May 19, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2029

Study Registration Dates

• First Submitted: November 19, 2025
• First Submitted That Met QC Criteria: December 8, 2025
• First Posted (Actual): December 16, 2025

Study Record Updates

• Last Update Posted (Actual): May 27, 2026
• Last Update Submitted That Met QC Criteria: May 22, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Type 1 Diabetes; Continuous glucose monitoring; Insulin pump; Tirzepatide; Automated insulin delivery; Hybrid closed-loop system; Closed-loop insulin delivery; Mounjaro; Overweight or obesity in type 1 diabetes; GIP/GLP-1 receptor agonist; Dual incretin therapy; Adjunctive tirzepatide therapy; Tandem Control-IQ; Dexcom G7
• Additional Relevant MeSH Terms: Endocrine System Diseases; Nutrition Disorders; Metabolic Diseases; Overnutrition; Body Weight; Autoimmune Diseases; Immune System Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Diabetes Mellitus, Type 1; Amino Acids, Peptides, and Proteins; Proteins; Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptide Receptors; Receptors, G-Protein-Coupled; Receptors, Cell Surface; Membrane Proteins; Receptors, Gastrointestinal Hormone; Receptors, Peptide; Tirzepatide
• Other Study ID Numbers: 2026-12143

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data may be shared with qualified researchers after completion of the trial and publication of the primary results. Shared data may include de-identified demographic variables, glucose and insulin delivery data, laboratory results, questionnaire scores, and device-based assessments collected during the study. All data will be reviewed to minimize re-identification risk in accordance with Canadian and Swiss privacy regulations. Researchers must submit a scientifically valid proposal and sign a data use agreement. Requests will be reviewed by the study team, and approved data will be provided through a secure transfer process.
• IPD Sharing Time Frame: IPD will be made available beginning 12 months after publication of the primary results and for a period of five years thereafter.
• IPD Sharing Access Criteria: Researchers must submit a scientifically valid proposal and sign a data use agreement.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes