Myelin repair and stem cells get attention at AAN Meeting

Tremendous advances in the understanding and treatment of MS were presented last week at the AAN Meeting in Vancouver. (Feel free to browse summaries of the presentations here – no registration is required). One of the areas getting the most attention was myelin repair. Myelin wraps around nerve fibers, like insulation on an electric cord. In MS the myelin is damaged, disrupting electrical signaling and making the nerves more susceptible to damage that leads to progression. Myelin repair is seen as a promising approach for restoring lost function and slowing down – or even stopping – progression.
We have recently come to learn that the brain is full of spare cells waiting to be called into the service of repairing myelin. In early MS, these cells find their way to areas of damage, wrap around nerve fibers and repair myelin. However, as the years go by, they lose this ability. Finding ways to stimulate the brain's ability to repair itself is an area of intense study and several notable presentations were made at last week’s meeting.
First, I would like to share they very promising work presented by Dr. Ari Green of the University of California, San Francisco. As announced late last week, he led a small, phase II proof of concept clinical trial to test whether an over-the-counter allergy medication, called clemastine, could promote myelin repair. The team measured the speed of nerve transmission in the optic (eye) nerve because it’s is easy to measure and is a very good indicator that myelin repair has occurred. Participants in the trial had a history of optic neuritis, where the myelin in the optic nerve is damaged.
In this trial, the nerve signaling speed increased when the participants were taking clemastine. This increase in nerve signaling is a strong indication that myelin repair has occurred. It is important to note that the dose used in the study exceeded the maximum recommended dose and was accompanied by side effects including fatigue. While it might be tempting, I would not recommend taking this medication until we know more about the risks and benefits. If you decide to not take this advice, I urge you to talk with your healthcare provider before taking any new medication.
You might be interested to know that the idea of promoting myelin repair with an anti-histamine drug came from MS Society sponsored research performed by Dr. Jonah Chan (a colleague of Dr. Green’s from UCSF). Dr. Chan discovered that myelin-making cells would wrap myelin around artificial nerve fibers as long as they were the proper size and the cells were properly stimulated. This discovery lead to a sophisticated screening tool that enabled the team to test whether any of thousands of FDA-approved medicines could stimulate myelin-making cells to grow new myelin. This screening tool identified clemastine as having myelin repair potential, and earned Dr. Chan the first Barancik Prize for Innovation in MS Research.
There are a number of other myelin repair agents in clinical trials for MS, and many others in pre-clinical testing stages that look like they are getting ready for first tests in people. So this area of research is really taking off.   
Another approach to myelin repair is the transplantation of myelin repair promoting stem cells. Advances in this approach were reported by Dr. Saud Sadiq from the Tisch MS Center in New York, who is attempting to promote myelin repair by transplantation of bone marrow derived stem cells into the spinal cord. Dr. Sadiq presented preliminary findings from treatment of 13 people with progressive forms of MS. He reported no serious adverse events so far (the trial has not yet been completed). There are also hints that some people may be responding to the treatment. But the trial is not designed to detect a clinical benefit, so caution should be used when interpreting these results. I look forward to the completion of this study and the publication of the full results.
Because the treatment so far, appears to be safe, the team has announced plans to advance this treatment to a phase II trial. Phase II trials are designed to provide evidence for effectiveness (as well as safety). I applaud Dr. Sadiq for his efforts to explore this innovative approach to the treatment of progressive MS, a form of MS that currently has no disease modifying treatment.  

If you’re interested to learn more about stem cells in MS, I encourage you to read about this and other approaches to stem cell therapy here
Highlights of MS-related presentations focusing on stopping MS, restoring function, and ending MS forever from AAN Meeting
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Bruce Bebo, PhD

Bruce Bebo, PhD, is Executive Vice President, Research at the National MS Society, and was previously a research immunologist focusing on the influence of sex hormones on MS. He is a driven and passionate Society volunteer, successful fundraiser and advocate, fueled in part by the fact that his mother had MS.