Biotin, a vitamin that helps cells to produce energy, boosts nerve function in high doses, opening the door to a possible treatment for progressive forms of multiple sclerosis.

Promising results of a pivotal study using high doses of the vitamin biotin in people with progressive forms of multiple sclerosis (MS) were recently presented at the Clinical Trials Plenary Session during the American Academy of Neurology (AAN) 67th annual meeting.

According to the study, one hypothesis to explain the cause of progressive MS is a phenomenon called “virtual hypoxia.”

The phenomenon is caused by a mismatch between increased energy demand by the damaged nerves and decreased energy production because of damage to the mitochondria. The mitochondria’s job is to manufacture fuel for the nerve cells to function properly. Biotin helps to make this happen.

Researchers wondered if giving patients high doses of biotin would help the damaged nerve cells to function better.

The year-long phase III study, conducted at multiple sites in France, was placebo-controlled, double blind, and involved 154 patients diagnosed with secondary or primary progressive MS.

Their baseline level of disability was determined using the Expanded Disability Status Scale (EDSS), a neurological exam that measures mobility, reflexes, vision, sensation, and cognition, among other things. For this experiment, all of the participants scored between 4.5 and 7 on the EDSS and had experienced worsening of their disease during the previous year.

Researchers wanted to see how many patients showed improvement in either their EDSS score, or in the measure of their timed 25-foot walk (TW25), after nine months of being treated with the investigational drug MD1003, a 300-milligram daily dose of biotin.

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Patients were evaluated using different methods, depending on the study site. Some sites relied on visual evoked potential (VEP) in patients with visual symptoms, while other centers used the EDSS or TW25 to detect changes in disability.

A small group of patient EDSS evaluations were videotaped at baseline and again at the end of the study. These videos were reviewed by an independent examiner specializing in MS motor disability who determined the difference in EDSS score between the before and after videos. The examiner didn’t know which video was which.

Overall, 91 percent of patients given high doses of biotin saw some clinical improvement in their condition.

“We are encouraged that the primary endpoint was met despite the very high bar for treatment response. This result…suggests that MD1003 could be an important and efficacious treatment for primary and secondary progressive multiple sclerosis,” said Ayman Tourbah, principal investigator of the study and a neurology professor at CHU de Reims in France, in a press release.

“The trial design and dosing were discussed with U.S. and European regulators, and we are pleased the results demonstrate evidence of improvement at one year in patients with progressive worsening MS,” said Dr. Frédéric Sedel, chief executive officer of MedDay Pharmaceuticals, the company that sponsored the study.

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The idea for studying biotin as a treatment for progressive MS came about after an earlier trial in patients with a rare genetic disorder called biotin-responsive basal ganglia disease (BBGD).

Patients diagnosed with BBGD have severe episodes of encephalopathy, a brain malfunction that often leads to death or permanent disability. Trials with BBGD patients showed dramatic improvement when they were given high doses of biotin along with thiamine.

A later study, in which Sedel was lead investigator, looked at biotin for patients with either optic neuritis or leukoencephalopathy and also showed promising results. It was later discovered that a patient in the study had secondary progressive MS.

From that discovery the leap to try high doses of biotin in progressive MS — for which no effective therapies currently exist — was made.

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Biotin (also known as vitamin H) is part of the B-complex group of vitamins that help the body convert food into fuel. Healthy skin, hair, eyes, and liver depend on B-complex vitamins, and, according to the University of Maryland Medical Center’s website, “They also help the nervous system function properly.”

Although it’s rare to be biotin-deficient, symptoms can include hair loss, dry eyes, dry or scaly skin, fatigue, and insomnia. Certain conditions such as Crohn’s disease can lead to biotin deficiency due to problems with vitamin absorption.

Since there is potential for drug interaction, you should consult your doctor before you start supplementing with biotin.

Long-term use of antibiotics can kill certain gut bacteria responsible for biotin production, and anti-seizure medications can lower biotin levels in the body.

Even in high doses, this water-soluble B vitamin doesn’t have any known side effects and is considered to be nontoxic.