New Therapy Using Antibiotic Proves Potentially Useful in Treating MS

Author:  Falishia Sloan

Institution:  Eastern Virginia Medical School
Date:  January 2008

Current research from scientists at Louisiana State University published in the February 2008 print issue of Archives of Neurology (one of the JAMA/Archives journals) has shown that combining a traditionally used medication against multiple sclerosis with an antibiotic may prove to slow the progress of the disease.

According to the authors of this preliminary study, "There is growing interest in combination therapy in patients with MS to stabilize the clinical course, reduce the rate of clinical relapses and decelerate the progressive course of the underlying pathologic mechanism."

Multiple sclerosis (MS) is a neurological disorder marked by the destruction of myelin, the insulating fatty tissue that covers axons of neurons in the central nervous system, which consists of the brain, spinal cord, and optic nerve. Axons act to propagate neurological electrical impulses from the brain to the body to result in movement of a body part, such as in walking. The destruction of the myelin leaves scar tissue called "sclerosis," and these lesions on the axons of the brain and spinal cord impede the progress of electrical signals from the brain to the body that govern movement, slowing down and sometimes stopping the progress of these signals to the point of disability for people with multiple sclerosis.

There are various forms of multiple sclerosis that dictate the experience of the people who have this disease. The most common type, relapsing-remitting MS, is marked by periods of remission, or generally symptom-free periods of the disease, in which patients do not experience symptoms and at times regain all or some of the function lost during the active portion of the disease. This active portion of the disease is the "relapse," which is marked by symptoms such as numbness and tingling in parts of the body. Through progression, the disease can result in partial or complete loss of neurological function in some cases.

The antibiotic used in the study, doxycycline, is part of the tetracycline antibiotic family. This antibiotic may be useful in treating MS and other inflammatory diseases because of its ability to inhibit the activity of harmful enzymes that destroy some cells of the CNS. Protection from this destruction characteristic in MS may result in protection of the brain and an increase in the effectiveness of the immune system.


This preliminary study involved15 patients with an average age of 44.5, who had relapsing-remitting MS and who had been experiencing symptoms characteristic of developing new brain lesions. All of these patients had also been taking interferon, a common drug used to impede the effects of multiple sclerosis.

For a duration of four months, patients took 100 mg of doxycyline daily in addition to their regular interferon dosages. Each month, the patients were given neurological examinations, as well as MRIs that were taken of their brains to observe brain lesions and blood work to monitor safety.

After the four month period, the scientists found that 60% of the patients experienced more than a 25% decrease in the number of lesions detectable by MRI than when they'd started. On a scale designed to assess levels of disability, these patients were also found to have reduced average scores. In addition, adverse effects experienced during the study were only those known to be associated with either the interferon or the antibiotic,no new adverse effects had resulted from the combination of taking the two together. Only one patient relapsed during the study.

"Overall, data from this cohort suggest that the treatment combination of oral doxycycline and interferon beta-1a may be safe and effective in some patients with MS;" the authors state. "However, further controlled clinical trials are warranted to demonstrate safety and efficacy in a larger patient population."

Written by Falishia Sloan

Reviewed by Emma Wear

Published by Pooja Ghatalia.