Early results from a Cambridge-led trial suggest that combining a common diabetes drug with an antihistamine may help repair nerve damage in multiple sclerosis (MS).
The study tested metformin, widely used for type 2 diabetes, alongside clemastine, an antihistamine previously shown to boost myelin repair. Myelin is the fatty protective sheath around nerves that is attacked in MS, leading to slowed or blocked electrical signals and progressive disability.
Seventy patients with relapsing MS took part in the CCMR Two trial. Over six months, those receiving the drug combination showed faster electrical signals between the eyes and brain than those on placebo, suggesting partial remyelination. However, the improvement—just 1.3 milliseconds—was too small for patients to notice any change in vision or daily function.
Dr Nick Cunniffe, who led the trial at the University of Cambridge, called the findings “exciting,” pointing to the potential of an entirely new class of therapies. “The drugs have a biological effect to promote remyelination, but people do not feel better on these drugs over six months,” he said.
Emma Gray of the MS Society described the outcome as a positive proof of concept, stressing that longer trials are needed to see real clinical benefits. Side effects, including fatigue and diarrhoea, were noted, and researchers warned against attempting the treatment outside clinical settings.
Globally, nearly 3 million people live with MS, most diagnosed in early adulthood. Current therapies focus on reducing immune attacks, but none directly restore lost myelin. Experts such as Jonah Chan of UCSF emphasised that remyelination remains “the critical path to preventing permanent disability” and restoring function in MS.
The results mark an early step, but researchers hope they could pave the way for drugs that not only slow the disease but also help repair its damage.
