26 September 2025

Early findings from a clinical trial in Cambridge suggest a combination of metformin, a diabetes drug, and clemastine, an antihistamine, can help repair myelin – the protective coating around nerves, which gets damaged in multiple sclerosis (MS) causing symptoms like fatigue, pain, spasms and problems with walking.

The CCMR-Two trial, which was carried out by researchers at the University of Cambridge supported by NIHR Cambridge BRC,  NIHR Cambridge Clinical Research Facility and Cambridge University Hospitals, offers real hope of stopping MS progression. The trial was also supported by the MS Society.

Previous evidence from studies showed that metformin enhances the effect of clemastine on myelin repair, but until now the two drugs had never been tested together in people. News of the latest trial was presented at this year’s European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) – one of the world’s biggest MS research conferences – in Barcelona on Friday 26 September.

Over 150,000 people live with MS in the UK. While there are around 20 disease modifying therapies or people with relapsing MS, and some emerging for active progressive MS, tens of thousands of people remain without effective treatment. Those drugs that do exist only work on one aspect of the condition – the immune system. They don’t stop the gradual nerve damage that leads to long-term disability. The research in Cambridge has offered fresh hope to thousands affected by MS that life-changing treatment could be on the horizon.

Researchers stress people should not attempt to acquire the drugs outside a clinical trial, as further research is needed to fully understand their efficacy and safety in MS.

Dr Nick Cunniffe, Academic Neurologist at the University of Cambridge, who led the CCMR-Two trial, says: “

I am increasingly sure that remyelination is part of the solution to stopping progressive disability in MS. We still need to research the long-term benefits and side effects before people with MS consider taking these drugs. But my instinct is that we are on the brink of a new class of treatments to stop MS progression, and within the next decade we could see the first licensed treatment that repairs myelin and improves the lives of people living with MS.”

Hannah Threlfell, 43, from Abington was diagnosed with relapsing MS in 2019 after experiencing optic neuritis. She joined the CCMR-Two trial in the hope she could help future generations. She said

 “Before I was diagnosed, I sat through a talk from MS specialist, Professor Alasdair Coles, about groundbreaking MS research. Even though I didn’t know I had it then, I remember thinking how incredible it was that so much had been achieved. And now I have MS, joining the trial was a no brainer. The team have all been so positive and amazing – I’ve made friends for life!

“I love helping and I know being on this trial will make a difference to someone else in the future – even small ripples have long-lasting effects! It would mean everything to find a way to stop MS progressing and would be the answer to the pray. This research gives me even more reason to believe that in my lifetime everyone with MS will have treatments that work for them.”

Director of Research, Dr Emma Gray at the MS Society, said

“These results are truly exciting, and could represent a turning point in the way MS is treated.  We desperately need ways to protect nerves from damage and repair lost myelin, and this research gives us real hope that myelin repair drugs will be part of the armoury of MS treatments in the future.

“This research is the culmination of decades of research funded by MS Society supporters. We won’t stop until we find treatments for everyone living with MS.”

The CCMR-Two trial is now closed. If you are interested in taking part in research and would like to find out more please visit the NIHR Be Part Of Research Website.