A vaccine that is used to prevent tuberculosis may help prevent multiple sclerosis (MS) in persons who show the beginning signs of the disease, according to a new study.
Ristori and colleagues at the “Sapienza” University of Rome and other centers studied 73 persons who had a first episode, or clinically isolated syndrome (CIS), that was suggestive of MS—with numbness, vision problems, or problems with balance—and had MRI scan findings that showed signs of possible MS. Definite MS develops in about half of persons with CIS within 2 years; 10% have no more MS-related problems.
Of the 73 study patients, 33 received 1 injection of a live vaccine, BCG, and the other 40 received a placebo. All underwent brain scans once a month for 6 months. They received the MS drug interferon-β1a for 1 year and then the MS drug recommended by their neurologist. The development of definite MS was evaluated for 5 years after the start of the study.
After the first 6 months, the patients who received the vaccine had 3 brain lesions that are signs of MS compared with 7 lesions for those who received the placebo. By the end of the study, MS had not developed in 58% of the vaccinated patients compared with 30% of unvaccinated patients.
There were no major adverse effects during the study, and there was no difference in adverse effects between patients who received the vaccine and those who did not.
The BCG vaccine is used to prevent tuberculosis in other countries but not for that purpose in the United States, it was noted.
More research needs to be done to learn more about the safety and long-term effects of this live vaccine, according to study authors. Doctors should not start using the vaccine to treat patients with MS or CIS, they suggested.
The study was published in the December 4, 2013, online issue of Neurology.
The results support the “hygiene hypothesis,” according to the authors of an accompanying editorial—that better sanitation and use of disinfectants and antibiotics may account for some of the increased rates of MS and other immune system diseases in North America and much of Europe compared with the rates in Africa, South America, and parts of Asia.