Generic Antibiotic May Reduce Progression to Multiple Sclerosis
Canadian researchers have found that a generic antibiotic may reduce progression to multiple sclerosis after a person’s first demyelinating event. According to Luanne Metz, MD, of the University of Calgary and one of the study’s authors, “It’s a well-tolerated drug that requires no safety monitoring whatsoever.”
The drug is minocycline, a broad-spectrum tetracycline antibiotic that is used to treat acne, pneumonia and other respiratory infections, as well as infections of the skin, urinary, and genital systems. Numerous studies have explored its use in schizophrenia and in neurodegenerative diseases such as multiple sclerosis, Parkinson’s disease, and Huntington’s disease.
The results of the phase III multicenter study were presented at the European Committee for the Treatment and Research in Multiple Sclerosis meeting in Barcelona. Overall, the investigators found that use of minocycline in the named participants results in a 44.6 percent risk reduction in progressing to multiple sclerosis over six months.
Individuals who experience their first demyelinating event (clinically isolated syndrome) can be started on various therapies that can present safety concerns as well as problems with insurance (which may not cover the drugs) as well as other cost constraints. Minocycline, in addition to demonstrating an ability to reduce progression, also is widely available, has a recognized safety profile, and is available in generic form, which lowers cost.
In the study, 142 adults (mean age, 35.8 years) who had experienced their first demyelinating event no more than six months before they entered the study and who had at least two T2 lesions confirmed by brain magnetic resonance imaging (MRI) were enrolled. The median expanded disability status scale (EDSS) score was 1.5
Participants were randomly assigned to take either placebo or 100 mg of oral minocycline twice daily for 24 months or until they developed multiple sclerosis. The primary outcome was the proportion of individuals who developed the disease by six months.
Here’s what they found:
- At six months, the risk of progression to multiple sclerosis was 61.4 percent in the placebo group and 34 percent in the minocycline group. This equals a 44.6 percent relative risk reduction and an absolute risk reduction of 27.4 percent
- At one year, the absolute risk reduction was 25.1 percent and relative risk reduction as 37.6 percent
- At 2 years, there was no significant difference between groups
- No unexpected safety issues were reported
Note: Relative risk tells you how much more or less likely the disease will develop in one group compared to another. Absolute risk is the overall likelihood of the disease developing.
According to Metz, minocycline should be considered as the first treatment as well as for combination therapy trials. For individuals who have clinically isolated syndrome, use of minocycline could be an alternative to starting other drugs.
Dennis Bourdette, MD, of Oregon Health & Science University, who was not involved in the study, told MedPage Today that minocycline “would be a good alternative for CIS [clinically isolated syndrome],” and could be especially helpful for CIS patients who “don’t want to go on anything yet, particularly the expensive drugs, which are either injectable or oral but have side effects.”
Since minocycline is relatively safe (mild gastrointestinal symptoms, dizziness, rash, tiredness) and much less expensive than other drug options, this antibiotic could be prescribed as a preventive measure against progression to multiple sclerosis for individuals who want to consider this approach.
Metz LM et al. Minocycline reduces the relative risk of multiple sclerosis in people experiencing their first clinical demyelinating event by 44.6%; results of a phase III double-blind placebo controlled Canadian multi-center clinical trial. European Committee for the Treatment and Research in Multiple Sclerosis, 2015. Abstract 2359