Leicester-led trial tests diabetes drug as potential aneurysm treatment
Researchers hope metformin could help treat a life-threatening condition affecting the body’s largest artery
A collaborative trial led by the University of Leicester is investigating whether a widely-used and affordable diabetes drug, metformin, could become the first ever drug treatment for abdominal aortic aneurysms – a condition responsible for approximately 4,000 deaths annually in the UK.
abdominal aortic aneurysms (AAAs) are balloon-like swellings in the body’s largest artery, the aorta, which carries blood from the heart through the abdomen. While small aneurysms are closely monitored with regular scans, larger ones carry a much higher risk of rupture, which can lead to fatal internal bleeding. The goal of the trial is to test if metformin, commonly prescribed for type-2 diabetes, can help prevent the growth of these aneurysms and spare patients from major surgical procedures.
Leading the trial
The £1.2 million trial, which represents a collaboration between researchers across the UK, Australia, and New Zealand, is aiming to recruit 1,000 patients over two years. Led from the University of Leicester, with research centres in Edinburgh, Oxford, Leeds, Bristol and London, this study is the largest drug trial ever conducted for AAA.
Professor Matt Bown, BHF Professor of Vascular Surgery at the University of Leicester, explained why metformin was selected: "Evidence suggests metformin could be the treatment for AAA we've long been looking for.
“Research in the lab indicates it could be working to prevent AAA growth by blocking inflammation in the aorta, a key factor that causes AAA enlargement."
A farmer joins the trial
East Midlands farmer Philip Gosling, 80, became the first person in the UK recruited to the trial after his 4cm-wide AAA was detected during a routine screening earlier this year.
Philip, who still works on his family farm, said: "I’m glad to be on the trial. I believe in research, I see the results of it every day on the farm, where science has changed things so much from when I started.
“When they told me about the trial, I had to get involved."
Philip is participating in the trial’s second stage, taking either metformin or a placebo daily and attending regular check-ups to monitor the growth of his AAA.
“My condition is very closely monitored, which can only be a good thing. Hopefully it will help a lot of people like me in the future," he said.
Why AAA patients need new treatment
For people with a smaller aneurysm like Philip, treatment is not given, and the condition is closely monitored through routine scans. However, up to 70 per cent of small AAAs eventually grow to over 5.5cm – roughly the size of a lime – when they are considered high-risk and require surgery.
The NHS offers screening for all men aged 65 and older, as they are most at risk. Women are less likely to develop AAAs, but they are more likely to have cases that are untreatable due to the shape, size, or position of the aneurysm.
At present, surgery is the main option for larger AAAs, but this comes with significant risks and is only considered when the aneurysm has grown to a dangerous size or has ruptured. Research has shown that patients with diabetes who are already taking metformin see reduced aneurysm growth rates, rupture rates, and fewer surgical repairs. However, the study is testing whether these findings can apply to individuals without diabetes.
Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, explained the significance of the trial:
“To date, we don't have effective drug treatments to limit the expansion of these aneurysms. This is the reason the BHF is supporting this important trial to determine whether a commonly available medication, metformin, usually used for the treatment of diabetes, can limit the expansion of these aneurysms and thus, reduce the risk of rupture."
"This important clinical trial will reveal whether this simple treatment can stop aneurysm growth and if it does, this would be a major breakthrough, providing reassurance for patients affected by this condition."
Offering hope for the future
If successful, the trial could pave the way for a non-surgical treatment for AAA, providing much-needed alternatives for patients who are unable to undergo surgery or wish to avoid invasive procedures.
Professor Bown added: "This trial will involve people who can currently do nothing but wait for their aneurysm to grow to a dangerous size. We hope we will prove that daily metformin can be used to treat this group and give them some much-needed peace of mind."
Results from the trial will show whether metformin helps to slow or stop aneurysm growth in patients who do not have diabetes, bringing new hope to thousands of people who live with the condition across the UK each year.