Early findings from a Cambridge-led trial suggest a promising new approach to treating multiple sclerosis (MS). Researchers found that combining a common diabetes drug, metformin, with the antihistamine clemastine may help repair myelin, the protective coating around nerves that is damaged in MS.
The CCMR Two trial, funded by the MS Society, recruited 70 patients with relapsing MS. Over six months, those given the drug combination showed small but measurable improvements in nerve signal transmission compared with those on a placebo.
Although the improvement – 1.3 milliseconds faster electrical signals between the eyes and brain – was too subtle for patients to notice in vision or disability changes, scientists say it proves the drugs have a biological effect on remyelination.
Dr Nick Cunniffe, who led the trial at the University of Cambridge, called the results encouraging: “I feel like we’re at this precipice of a new class of therapies for MS and that’s why this is exciting.”
Nearly 3 million people worldwide live with MS, including more than 150,000 in the UK. Current treatments focus on slowing immune attacks, but none directly repair lost myelin. Researchers hope remyelination drugs could prevent long-term disability and, in some cases, restore function.
Emma Gray, research director at the MS Society, said the findings were an important proof of concept: “We would not expect them to have a clinical benefit after only six months. It will take longer for this to be seen.”
However, both clemastine and metformin caused side effects, including fatigue and diarrhoea, and experts warn that patients should not attempt to access the drugs outside clinical trials.
Jonah Chan, a neurology professor at UCSF, said the work strengthens the case for remyelination research: “I’m more convinced than ever that remyelination is the critical path to preventing permanent disability in MS.”
Larger, longer trials will be needed to confirm whether these therapies can deliver meaningful improvements in patients’ daily lives.
