A major clinical trial has kicked off in Scotland to investigate prophylactic use of metformin as a means of staving off type I diabetes in children.

The study, which is backed by initial funding of £1.7 million from JDRF, aims to contact all 6,400 families in Scotland affected by the condition, with a view to expanding into England at a later date.

Children aged five to 16 who have a sibling or parent with type I diabetes will be invited for a blood test to establish whether they are at high risk of developing the disease and wish to take part in the trial. Researchers led by Professor Terence Wilkin, of the University of Exeter Medical School, will then examine the impact of administering the world’s most commonly prescribed diabetes medicine metformin to those in the high-risk category.

The incidence of type 1 diabetes has risen five-fold in the last 40 years. It was widely believed that the condition is an autoimmune disease caused by a faulty immune system which attacks and destroys insulin-producing beta cells in the pancreas. However, this has, thus far, not been backed by data from clinical trials involving immunosuppressants.

The Accelerator Prevention Trial (adAPT) is the first to test an alternative explanation, based on the accelerator hypothesis put forward by Professor Wilkin in 2001. This suggests that autoimmunity occurs as a response to damaged beta cells, which have been “made to work to hard in modern environment”. adAPT will test whether metformin, which protects beta cells from stress, can stop this destructive immune response.

“It is possible that a modern environment accelerates the loss of beta cells by overworking and stressing them,” continued Professor Wilkin. “As a consequence, this could be contributing to the rising incidence of type I diabetes, which is appearing in ever younger age groups.” 

Around 80,000 children are estimated to develop type I diabetes worldwide each year. As yet there is no way to prevent it and no cure, leaving patients facing a lifetime of strict dietary controls and multiple daily insulin injections. “If successful, the trial will offer a means of preventing type I diabetes with a cost-effective medication, and could be made immediately available to children at risk,” he noted.

The trial is launching in Scotland because it has the third highest rate of the disease in the world. Tayside is the first centre to start patient enrolment, but the study will roll out to the other 10 health boards in the country before crossing into England.