First person with MS joins new myelin repair trial

In 2020, results from a small trial suggested an existing cancer drug could promote myelin repair in people with relapsing MS. Unfortunately, the side effects were too severe for the drug to be taken forward. But we announced plans for a new trial to build on these findings.

In 2022, after some delays due to COVID-19, the first person joined the new trial. The trial will test two drugs in combination to see if they can kickstart the body’s natural myelin repair process. 

"It's given me so much hope"

The first person to join the trial was Annabelle, who was diagnosed with relapsing MS in 2011. While on the trial she’ll take daily tablets of either the treatment combination, or a placebo (dummy drug), for six months. She’ll have MRI scans to look at the amount of myelin in existing areas of damage. And a visual test that can measure how fast messages are traveling between the eyes and the brain. Both of these should improve if the myelin is repaired.

Annabelle says: “I was so inspired when I saw the clinical trial and signed up straight away… just a few months ago I was told there was nothing I could do – now I’m the first participant on a new trial! It’s given me so much hope.”

Professor Alasdair Coles, from the University of Cambridge, is leading the trial. He says: “The recruitment of our first participant is a huge milestone. We’re another step closer to a time where a person with MS will be given a handful of treatments to tackle all the different elements of MS, so that their life will be minimally affected by the condition.”

Repurposing existing diabetes and hayfever drugs

The trial is testing two drugs in combination:

• Metformin is an existing diabetes treatment.  
• Clemastine is an antihistimine used to treat hayfever.

They’ve both shown promise in the lab for their effects on myelin. In rats, metformin can help myelin-making cells better at repair by mimicking the effects of fasting. And, in a small group of people with MS, clemastine improved the speed of messages from the eye to the brain alongside a disease modifying therapy (DMT). Other animal studies have also shown metformin may enhance the effect of clemastine.

Researchers hope combining these two drugs could provide a safe and effective myelin repair treatment. Because these are both used already for other conditions, we already understand many of their side effects. But the combination has never been tested before in people. And metformin has never been tested in people with MS. So we need a trial to find out if it's safe and effective.

Who can take part in the trial?

This is a small trial. Only 50 people will take part. Most people will be recruited through Addenbrookes Hospital in Cambridge.

Everyone taking part will have relapsing MS. This is because in relapsing MS, more nerves are healthy enough for repair to happen. So researchers have a better chance of seeing an effect. If they find the treatment promotes myelin repair, a next step could be to test this in people with progressive MS.

Finding treatments to stop MS is our number one priority.

One year after the trial started, the team have recruited more than half of the participants they need. Once everyone in the trial has completed the six months of tablets, the team can start to put together the results. 

Our Head of Research, Dr Clare Walton, says: “While there are over a dozen licensed treatments for people with relapsing forms of MS, there are still lots of people without treatment.

"This new research really is a major milestone in our plan to stop MS and we’re excited to get the results.”

This story was updated in April 2023