MS is a chronic, degenerative auto-immune disease, where the immune system attacks the myelin (fatty protective cover) that surrounds nerve cells, causing disability.

At first, the body is able to rebuild the myelin (remyelination) but over time, the damage becomes harder to repair, causing progressive and permanent disability.

Currently, there are no treatments that can boost myelin repair in MS. Researchers in Cambridge and Edinburgh had already shown that Bexarotene targets a protein in the brain that encourages myelin repair. Encouraged by this result, a study has been set up to see whether the drug could help the brain regenerate myelin in people with MS.

Fifty patients took part in the nine-month trial, which ended in May 2019; will help researchers understand if Bexarotene has potential as an MS treatment. To stop MS we need to find treatments that repair the damage to the protective myelin coating around nerves.

Cambridge researchers supported by the NIHR Cambridge BRC are also looking at the potential of diabetes drug Metformin to promote myelin repair in patients with progressive MS. This trial is due to open in 2020.

T and B white blood cells normally attack bacteria, but in patients with MS, these white blood cells attack the nerves in the brain and spinal cord. In trials done from 1991 to 2012, researchers found that alemtuzumab stopped the immune system from attacking these nerves. As a result, patients with multiple sclerosis did not get worse, and indeed often noticed an improvement in their disability; this has never been achieved before.

Alemtuzumab was licensed in Europe in 2013 and approved by NICE in 2014. It is now been licenced in over 50 countries, and administered to tens of thousands of people with multiple sclerosis.