THE QUESTION Might a vaccine used to prevent tuberculosis offer protection against multiple sclerosis as well?
THIS STUDY involved 82 adults (average age, 32) at high risk for developing multiple sclerosis because they had had an episode involving numbness, vision problems or balance problems — such an event is known as clinically isolated syndrome — and an MRI scan that showed signs suggestive of MS. They were randomly assigned to be injected with the bacille Calmette-Guerin (BCG) vaccine or a placebo within 90 days of that episode. After six months, all participants took the MS drug interferon beta-1a (Avonex) for a year and then took whatever MS medication their doctor prescribed. Brains scans six months after vaccination showed fewer lesions among those who had been given the BCG vaccine. After five years, 58 percent of those given the vaccine had experienced no further episodes, compared with 30 percent who got the placebo. No major side effects were reported.
WHO MAY BE AFFECTED? People with early signs of MS. About half of those with clinically isolated syndrome develop full-blown MS within two years. MS is a nervous system disease that causes messages between the brain and various parts of the body to be blocked or delayed, resulting in problems with vision, muscle control, balance, memory and more. MS is thought to be an autoimmune disease, meaning the immune system attacks the body rather than acting as its defense system, but what causes this to occur remains unknown.
CAVEATS The study did not determine how the BCG vaccine works against MS; the vaccine also is being tested against Type 1 diabetes. The study also did not test different dosages or whether multiple vaccinations might be more effective against a chronic disease such as MS. The study was too brief to assess long-term safety.
FIND THIS STUDY Dec. 4 online issue of Neurology.
LEARN MORE ABOUT multiple sclerosis at www.ninds.nih.gov.
The research described in Quick Study comes from credible, peer-
reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.