Epilepsy Drug May Help Reduce Disability from Multiple Sclerosis

Findings may lead to new treatment that protects nerves from damage caused in optic neuritis and throughout the central nervous system during MS attacks.

An epilepsy drug could offer a new treatment option for multiple sclerosis (MS) patients by protecting nerve damage.

A study published in Lancet Neurology found the drug phenytoin, an anti-convulsant drug that treats epilepsy, can protect neural tissue in patients with optic neuritis, which is a symptom of MS where nerves that transport information between the eyes to the brain becomes inflamed and damaged.

MS is a disease that attacks the central nervous system, which leads to confusion and delays messages transmitting from the brain and spine to the body. This can lead to loss of sight, fatigue, pain, continence, and disability. Symptoms for this disease typically appear in people in their 20s and 30s.

These experiments were performed by researchers at the UCL Institute of Neurology and were presented at the American Academy of Neurology 67th Annual Meeting.

Researchers evaluated 86 patients with acute optic neuritis who were administered either phenytoin or a placebo. The patients were evaluated using Optical Coherence Tomography (OCT) to measure the thickness of the retina and the nerve layer at the back of the eye that is sensitive to light.

The results of the study found that the phenytoin group had an average of 30% less damage to the nerve fiber layer compared with patients in the placebo group.

"These are promising results and if our findings are confirmed by larger, phase 3 trials, could lead to a new treatment that protects nerves from the damage caused both in optic neuritis and throughout the central nervous system in other attacks of MS," said researcher Dr. Raj Kapoor.

Researchers had been focusing on the sodium channels because in inflamed areas, the axons of nerve cells get flooded with sodium, which causes an influx of calcium leading to cell death. Investigators believe that if they are able to stop sodium from entering into the cell, they could prevent this from occurring.

"We wanted to find out if the theory that blocking sodium currents, which we developed in basic work over many years, actually served to protect neural tissue -- a test-bed to see if we can achieve neuroprotection," Dr. Kapoor said.

Discovering a new method to potentially treat MS patients left Dr. researchers with high hopes to prevent disaibility.

"We have been trying to achieve neuroprotection ever since we realized that disability was due to nerve damage, so it is very encouraging that we have now found one way of doing so,” Dr. Kapoor said. “We hope this will open the door to significant progress in preventing disability not only in optic neuritis, but also in MS as a whole."