A Cambridge-led clinical trial has shown that a diabetes drug combined with an antihistamine can partially repair nerve damage in people with multiple sclerosis (MS).
The CCMR Two study tested metformin, a common diabetes medication, alongside clemastine, an antihistamine previously linked to stimulating myelin repair. Seventy patients with relapsing MS took part, with half receiving the drug combination and half a placebo for six months.
Results showed modest improvements in nerve function, with electrical signals between the eye and brain travelling 1.3 milliseconds faster in the treatment group. However, patients did not experience noticeable improvements in vision or disability over the short trial period.
Lead researcher Dr Nick Cunniffe described the findings as a step toward a new class of MS therapies: “The drugs have a biological effect to promote remyelination, but we need to be clear that people do not feel better on these drugs over six months.”
Experts believe longer studies are needed to see clinical benefits. The MS Society, which funded the trial, called the results a “positive proof of concept” that warrants further investigation.
Globally, nearly 3 million people live with MS, which occurs when the immune system attacks the myelin coating around nerve cells. Current treatments focus mainly on slowing immune attacks rather than repairing damage.
While side effects such as fatigue and diarrhoea were reported, researchers stressed that patients should not attempt to self-medicate outside of trials.
Emma Gray of the MS Society said: “We would not expect clinical benefit after only six months. It will take longer for this to be seen.”
Neurologist Jonah Chan of the University of California added that remyelination remains the most promising path to preventing long-term disability: “We need to be inspired by optimism but comfortable with learning from setbacks.”
