LIMIT trial: Could metformin be first-ever medical treatment that is effective at managing aneurysm disease?

There is a global interest in assessing whether Metformin, which has a long track record of safety and efficacy, is relatively inexpensive and is taken by millions of people every day for type 2 diabetes, has an effect on the progression of abdominal aortic aneurysms (AAA).

The LIMIT trial, a prospective randomised level one, placebo-controlled, blinded trial, sponsored by the National Institutes of Health (NIH), is designed to investigate whether metformin significantly prevents the enlargement of existing AAAs in non-diabetic people.

“It is difficult to make an asymptomatic patient better. And so, you want a treatment that is not going to be very arduous, and not be very high risk. [It should be] relatively inexpensive, [and] easy to take, and metformin checks all those boxes,” explains Ronald L Dalman (Stanford, USA) at the 2023 VEITHsymposium (14–18 November, New York, USA), who invites the US vascular community to get involved in the trial.

“If Metformin works in this application, it may also work in secondary treatment after [a] patient has had endografting to reduce the need for secondary procedures for endoleaks, for graft migration, or aneurysm enlargement. It could be [used] in a variety of applications both as a de novo treatment, as well as an adjunctive treatment following surgery. Here is something that could be a complement to surgical management, both before during or after surgical intervention,” adds Dalman, who is the Walter C and Elsa R Chidester Professor and vice chair of Surgery for clinical affairs at Stanford Medicine. He is also the inaugural executive editor for the Journal of Vascular Surgery publications suite.