AuthorisedHuman Pharmacology (Phase I)- OtherInterventional

A multicentre, single-arm, open-label, non-randomised pilot clinical trial to assess the dose-dependent effect of tirzepatide on gastric emptying in adult patients with type 1 diabetes

Managing type 1 diabetes involves carefully matching insulin to the food you eat. How quickly your stomach empties after a meal plays a major role in how fast your blood sugar levels rise. In this small pilot study, researchers are testing a drug called tirzepatide in adults living with type 1 diabetes. Tirzepatide is already used for type 2 diabetes and weight management, and it is known to slow down digestion. The trial aims to find out exactly how different doses affect the rate of stomach emptying. Because this is an 'open-label' study, all participants will know what dose they are receiving, with no dummy treatments (placebos) used. The findings will help scientists learn whether tirzepatide could one day be safely used alongside insulin to help smooth out blood sugar spikes after meals.

At a glance

Status

Authorised

Phase

Human Pharmacology (Phase I)- Other

Sponsor

Fundacion Para La Investigacion Biomedica Del Hospital Universitario Ramon Y Cajal

Enrolment target

Start

18 Sep 2026

Type 1 Diabetes.

What is this study about?

When you have type 1 diabetes, your body cannot produce its own insulin. People with the condition must take insulin every day to balance their blood sugar levels, especially around mealtimes. However, blood sugar can still spike quickly after eating, partly because of how fast the stomach breaks down food and sends it into the gut.

Tirzepatide is an injectable medicine that works by mimicking natural gut hormones. In people with type 2 diabetes, it has been shown to slow down stomach emptying and help control blood sugar levels. Scientists now want to explore whether it might offer similar benefits for people living with type 1 diabetes, helping to prevent sharp rises in glucose after eating.

This pilot trial is a Phase 1 study, meaning it is one of the earliest stages of testing this medicine for this specific purpose. Researchers want to measure the exact effect of different doses on the speed of digestion, known as gastric emptying. By carefully tracking these changes, the research team can find out which doses are most effective and safe to explore in larger, future clinical trials.

It is important to understand that this study is not designed to replace your usual insulin. Instead, it is an exploratory step to see how the digestive system responds to the medicine, providing valuable scientific clues about how modern diabetes treatments might be improved.

Key takeaways

The trial tests how different doses of tirzepatide affect stomach emptying speed in type 1 diabetes.
This is an early-stage Phase 1 pilot study involving adults aged 18 and older.
Everyone in the study receives the active medication; no placebo is used.
You will need to continue your normal insulin routine throughout the trial.
Taking part is entirely voluntary and you can withdraw at any point.

Who may be eligible?

This trial is open to adults aged 18 and over who have been diagnosed with type 1 diabetes. Both men and women are able to join. Because it is a pilot trial, researchers are looking for a small group of volunteers who are generally stable on their current insulin routines.

Certain people may not be able to participate. For example, if you already have severe stomach or gut problems—such as diabetic gastroparesis, where the stomach naturally empties very slowly—you may not be eligible, as this could affect the test results. Those who are pregnant, breastfeeding, or planning a pregnancy are also usually excluded for safety reasons.

Before taking part, a doctor at the study centre will carefully check your medical history, current medications, and overall health to ensure that joining the study is safe for you.

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.

I am aged 18 or older.
I have been diagnosed with type 1 diabetes.
I am not currently pregnant or planning a pregnancy.
I do not have a history of severe stomach emptying disorders (such as gastroparesis).
I am able to attend regular appointments at a clinical research centre.

Answer every question to see your result.

What does participation involve?

Taking part in this study will involve several visits to a hospital or clinical research centre. First, you will attend a screening visit to check your eligibility, which will include blood tests and a review of your general health.

During the trial, you will receive doses of tirzepatide, which is given as an injection under the skin. You will be asked to attend test sessions where researchers measure how quickly your stomach empties after you eat a specially prepared meal. These tests are painless and often involve simple breath tests or gentle scans over a few hours.

Throughout the study, you will continue to monitor your blood sugar levels closely, and the study team will keep in regular contact to check for any side effects. The trial team will confirm the exact number of weeks the study will last before you decide to join.

Potential risks and benefits

Taking part may not directly cure or permanently change your diabetes, but it helps doctors discover new ways to manage blood sugar in the future. As with any medicine, tirzepatide can cause side effects. The most common are digestive issues such as mild nausea, feeling unusually full, or an upset stomach. Because it slows digestion, it may also change how your body absorbs food, which could alter your risk of low blood sugar (hypoglycaemia). The study team will monitor you very closely throughout the trial. Taking part is completely voluntary, and you are free to leave the study at any time without your regular NHS care being affected.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Spain

Common questions

What is tirzepatide?

Tirzepatide is an approved medicine for type 2 diabetes and weight loss that copies natural hormones to help manage blood sugar and slow down digestion.

Will I receive a placebo (dummy drug)?

No. This is an open-label study, which means every participant will receive the active study medicine and will know the dose they are taking.

Will I have to stop taking my regular insulin?

No. People with type 1 diabetes must always continue their essential insulin therapy. The study team will give you clear guidance on balancing your insulin.

How is stomach emptying measured?

Stomach emptying is typically measured by having you eat a test meal followed by non-invasive breath tests or gentle body scans to see how fast the meal moves through your stomach.

Do I have to pay to take part?

No, clinical trials run through UK research centres do not charge participants, and travel expenses are often covered.