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Large Observational Study Confirms Long-Term Benefits of MS Therapies for Reducing Relapses and Risk of Disability

January 7, 2021

An international team of investigators has reported results of an observational study involving over 14,000 people with relapsing-remitting MS, who were followed at various medical centers and countries for up to 15 years as part of the MSBase registry. They confirmed previous reports that long-term exposure to disease-modifying therapies reduces relapse activity and also prevents disability worsening.
  • The team looked at outcomes for people in the registry for periods of time on and periods of time off of treatment with MS disease-modifying therapies (largely interferons and glatiramer acetate rather than more recently available therapies).
  • Using complex statistical methods, they reported that during periods of time on treatment, people were significantly less likely to experience relapses and worsening of disability compared to periods of time off treatment. People treated early in the course of MS were more likely to experience reversal of some accumulated disability. Over 15 years, continued treatment reduced the frequency of relapses by 40% and reduced the risk of needing an aid for walking by 67%.
  • Observational studies such as this one cannot take the place of randomized, controlled clinical trials, but instead can offer real-world evidence of treatment effects by following outcomes in very large numbers of people over time. 
“Effect of Disease Modifying Therapy on Disability in Relapsing-Remitting Multiple Sclerosis Over 15 Years,” by Dr. Tomas Kalincik (University of Melbourne) and many others on behalf of the MS Base Study group, was published early online on December 28, 2020 in Neurology, the journal of the American Academy of Neurology.
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Disease-modifying therapies for MS
Non-pharmacological treatment approaches

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis, and there is currently no cure for MS. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. An estimated 1 million people live with MS in the United States. Most people with MS are diagnosed between the ages of 20 and 50, and it affects women three times more than men.


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