RecruitingPHASE2, PHASE3INTERVENTIONAL

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

This research is testing a weekly medicine called tirzepatide to see if it can make managing type 1 diabetes easier for adults using an insulin pump. Often, people with type 1 diabetes have to carefully count carbohydrates in their meals to give themselves the right amount of insulin. This can be challenging. Tirzepatide is already used for type 2 diabetes and weight loss, and it might help by slowing digestion and smoothing out blood sugar levels after eating. The study will see if people taking tirzepatide can keep their blood sugar well-controlled without needing to count carbs, compared to those who continue to count them.

At a glance

Status

Recruiting

Phase

PHASE2, PHASE3

Sponsor

McGill University Health Centre/Research Institute of the McGill University Health Centre

Enrolment target

105

Start

19 May 2026

Estimated completion

01 Jan 2029

Type 1 Diabetes Type 1 Diabetes Mellitus T1D T1DM T1DM - Type 1 Diabetes Mellitus

What is this study about?

Living with type 1 diabetes means you have to take insulin for your whole life. Even with modern insulin pumps and glucose monitors, it can still be tricky to keep blood sugar levels in the healthy range. One of the biggest difficulties is having to estimate the carbohydrates in everything you eat and drink, which helps you work out how much insulin you need at mealtimes. This can be time-consuming and stressful.

This study is looking at a medicine called tirzepatide. It's already approved in the UK for type 2 diabetes and for weight management. Researchers want to find out if it can help adults with type 1 diabetes. They think tirzepatide might make managing blood sugar easier by slowing down how quickly food leaves your stomach, reducing your appetite, lowering the amount of insulin you need, and preventing big jumps in blood sugar after meals.

The main goal of this study is to discover if people with type 1 diabetes who take tirzepatide can safely keep their blood sugar under control without needing to count carbohydrates for their meals, compared to those who continue with their usual carb-counting routine. If successful, this could make daily life much simpler and less stressful for many people with type 1 diabetes.

Key takeaways

Tests if tirzepatide can simplify type 1 diabetes management.
Aims to reduce or remove the need for carbohydrate counting.
Uses Tirzepatide (weekly injections) or standard care.
All participants use a specific insulin pump and glucose monitor.
Study lasts 32 weeks, with regular check-ups.
Potential for easier blood sugar control, but consider possible side effects.

Who may be eligible?

To join this study, you need to be an adult aged 18 or over and have been diagnosed with type 1 diabetes for at least one year. Your Body Mass Index (BMI) should be 27 or higher, and your HbA1c (a measure of average blood sugar over 2-3 months) needs to be between 6.5% and 12%. You should either be taking insulin through multiple daily injections or using an insulin pump, and you must be actively counting carbohydrates for your mealtimes.

You would not be able to join if you've recently used certain diabetes medications (like GLP1-RAs or other anti-hyperglycaemic drugs), or if you are pregnant, planning to get pregnant, or breastfeeding. Also, you can't have had severe low blood sugar requiring hospitalisation or diabetic ketoacidosis in the last two months. There are also exclusions for certain medical conditions like a history of pancreatitis, specific kidney issues, or a family history of a rare type of thyroid cancer.

All participants will need to use a specific type of insulin pump system (Tandem Control-IQ with Dexcom G7). If you are able to get pregnant, you must agree to use effective birth control throughout the study.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Have you had type 1 diabetes for at least one year?
Is your BMI (Body Mass Index) 27 or higher?
Are you actively counting carbohydrates for your meals?
Are you able to use a Tandem Control-IQ insulin pump with a Dexcom G7 sensor?
Are you not pregnant, planning to be, or breastfeeding?

Answer every question to see your result.

What does participation involve?

If you join this study, you will be using a specific insulin pump system called Tandem Control-IQ along with a Dexcom G7 continuous glucose monitor throughout the 32 weeks of the trial. You will be randomly put into one of two groups. If you're in the tirzepatide group, you'll receive weekly injections of the medicine, with the dose gradually increasing over 12 weeks. Eventually, you'll try using your insulin pump without entering carbohydrate amounts for your meals during the later part of the study.

If you're in the control group, you'll continue your usual routine of counting carbohydrates for your mealtime insulin doses. Both groups will attend several clinic visits and have remote check-ups during the 32 weeks. Researchers will collect information about your glucose levels, insulin use, and overall health. Some clinics might also ask you to do additional tests like heart/fitness assessments or body composition scans.

Potential risks and benefits

Taking part in this study could potentially make managing your type 1 diabetes easier, especially if it helps reduce or remove the need for carbohydrate counting. However, tirzepatide, like any medicine, can cause side effects. Common ones include feeling sick (nausea), being sick (vomiting), diarrhoea, or having a reduced appetite. Less common but more serious risks, such as gallbladder problems or inflammation of the pancreas (pancreatitis), will also be carefully monitored. You have the right to withdraw from the study at any time, for any reason, without it affecting your usual medical care.

Locations (4)

Institut de Recherches Cliniques de Montréal
Verified postcode
Montreal, Canada· Not yet recruiting
McGill University Health Centre
Verified postcode
Montreal, Canada· Not yet recruiting
Hygea Medical Clinic
Verified postcode
Montreal, Canada· Recruiting
Insel Hospital, University Hospital Bern
Verified postcode
Bern, Switzerland· Not yet recruiting

Common questions

What is tirzepatide?

Tirzepatide is a medicine already used for type 2 diabetes and weight loss that helps lower blood sugar and can reduce appetite and slow digestion.

Why are they studying this for type 1 diabetes?

Researchers want to see if tirzepatide can help simplify daily life for people with type 1 diabetes, especially by reducing the need to count carbs for meals.

Will I have to stop counting carbs if I join?

Only if you're in the tirzepatide group and only during the final 6 weeks of the study, after a gradual introduction. The control group will continue carb counting.

What are the common side effects of tirzepatide?

Common side effects include feeling sick (nausea), being sick (vomiting), diarrhoea, or having a reduced appetite.

How long will the study last?

The study will last for 32 weeks, with clinic visits and remote check-ups during that time.

How to find out more

Keddy Moise, MSc (candidate)

keddy.moise@mail.mcgill.ca 438-531-6896 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.