All studies
RecruitingPhase IIInterventional

Testing whether a commonly used drug to treat Diabetes can reduce injury to the lung following heart surgery and in critical illness.

This study is looking into whether a widely used diabetes medicine, called metformin, can help protect people's lungs during and after heart surgery. When patients have heart bypass surgery, their lungs can become a little inflamed. Researchers believe metformin might reduce this inflammation. They are doing this research to understand how metformin works in the body and if it could be used to treat a more severe lung condition called Acute Respiratory Distress Syndrome (ARDS), which currently has no cure. If metformin shows promise in protecting lungs during bypass surgery, it could lead to bigger studies for patients with ARDS. This is a Phase II study, meaning it's still in the early stages of testing in people.

At a glance

Status
Recruiting
Phase
Phase II
Sponsor
Belfast Health and Social Care Trust
Enrolment target
56
Start
09 Feb 2026
Estimated completion
01 Aug 2029

What is this study about?

This research wants to find out if a medicine called metformin, which is usually used to treat diabetes, can help protect people's lungs, especially after heart surgery. When someone has heart bypass surgery, their body can react with mild swelling or inflammation in the lungs. This study aims to see if metformin can reduce this inflammation and any minor damage to the lungs that might happen normally during this type of operation.

Why is this important? There's a very serious lung condition called Acute Respiratory Distress Syndrome (ARDS). In ARDS, the lungs get badly inflamed and fill with fluid, making it very hard to breathe. Sadly, there's no cure for ARDS right now. Scientists have found that metformin might help reduce inflammation in ways that could be useful for ARDS. By studying how metformin affects the lungs during heart surgery (where the inflammation is milder), researchers hope to learn if it could eventually be a treatment for ARDS. This study is an important step to gather information before larger trials involving ARDS patients.

This study will help researchers understand if metformin has the potential to keep lungs healthier and how best to design future studies for people with ARDS. It's about finding new ways to help those with serious lung problems.

Key takeaways

  • Exploring if a diabetes drug (metformin) can protect lungs during heart surgery.
  • Aims to learn more for a serious lung condition called ARDS.
  • Participants are adults having planned heart bypass surgery.
  • Involves taking metformin and some extra blood tests/a tiny muscle sample.
  • Common metformin side effects are tummy upsets, which usually improve.
  • Your health and safety are closely monitored during the study.

Who may be eligible?

This study is looking for adults who are 18 years old or older. You need to be planning to have a specific type of heart surgery called coronary artery bypass graft (CABG) where a heart-lung machine is used. This surgery must be scheduled, not an emergency.

You cannot take part if you are under 18 or if your surgery is planned so soon that you wouldn't be able to take the full course of metformin before it. People who already have diabetes and are on treatment for it, or who have certain kidney or liver problems, cannot join. If you have an untreated vitamin B12 deficiency or a known allergy to metformin, you also won't be able to participate. Lastly, if you've been part of another drug trial in the last 30 days, or can't take medicines by mouth before surgery, you won't be eligible.

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.

  1. Are you 18 years old or older?
  2. Are you having planned heart bypass surgery soon?
  3. Do you currently have diabetes and take medication for it?
  4. Do you have severe kidney or liver problems?
  5. Do you have an untreated vitamin B12 deficiency or known metformin allergy?
Answer every question to see your result.

What does participation involve?

If you decide to take part in this study, you will be given metformin. This medicine will be introduced gradually before your heart bypass surgery. While you are in the study, researchers will collect blood samples. Many of these samples will be taken at the same time as the routine blood tests you would have anyway for your surgery, to avoid extra needle sticks when possible. During your heart surgery, a very small piece of muscle will be taken from your chest area. This small sample is taken from a muscle that surgeons already see and work around during this type of operation, and it won't affect how your body works or add risk to your surgery. Your participation will last for the duration of your hospital stay and recovery related to the heart surgery.

Potential risks and benefits

Because this is an early-stage study, the full benefits of taking part are not yet known, but your participation will help researchers learn more about how metformin might protect lungs, potentially leading to new treatments for serious lung conditions in the future. The risks involve common side effects of metformin, such as tummy pain, sickness, or diarrhoea, which often get better on their own. The researchers will start the medicine slowly and use a gentle version to help lessen these effects. There’s a very small risk of infection or discomfort from blood tests, but many will be done during your routine checks. A very rare potential issue with metformin is a condition called lactic acidosis, but large studies have shown the risk isn't higher with metformin than without it, and the researchers will carefully check your health, especially your kidney function, to reduce this risk. You have the right to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.
  • -
    Unverified
    NO COUNTRY SPECIFIED, assuming England, England

Common questions

What is ARDS?

ARDS stands for Acute Respiratory Distress Syndrome. It's a very serious lung condition where the lungs become badly inflamed and fill with fluid, making it hard to breathe and often requiring a breathing machine.

What is metformin normally used for?

Metformin is a common medicine usually prescribed to people with type 2 diabetes to help control their blood sugar levels.

Will taking part affect my heart surgery?

The study procedures, like taking blood samples and a tiny muscle biopsy, are designed to fit in with your standard heart bypass surgery care and should not add extra risk or affect the surgery itself.

Where is this study happening?

This study is being run from the Belfast Health and Social Care Trust in the UK.

What if I change my mind about participating?

You can leave the study at any time, for any reason, without it affecting your medical treatment or care.

How to find out more

Jonathan Strickland

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

Discussion

Community discussion

Powered by our forum at community.patient.info. Please be respectful — this is not medical advice.