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International Committee Re-Examines Definitions of the Courses of MS

June 4, 2014

Multiple sclerosis manifests itself in many different ways and different courses, and the path of an individual’s MS is usually defined by patterns of symptoms, such as whether they come and go or remain or get worse. Having more refined definitions of different types of MS would greatly facilitate research studies, communications between people with MS and their healthcare providers, and treatment decisions. For these reasons, a recent effort to fine-tune descriptions of MS was undertaken by the International Advisory Committee on Clinical Trials in MS. This committee is comprised of international leaders in MS research and clinical care and is jointly supported by the National MS Society and the European Committee for Treatment and Research in MS (ECTRIMS). A summary of the deliberations, including recommendations for more research, has just been published and can be read or downloaded without fees (Neurology, published ahead of print May 28, 2014).

Why was this effort undertaken?
In 1996 the Committee had developed consensus around descriptions, or “phenotypes,” of the courses of MS to facilitate research in MS and so that researchers and clinicians around the world would have a common understanding of the types of MS discussed in publications and in the clinic. This consensus highlighted four courses of MS -- relapsing-remitting, secondary progressive, primary progressive, and progressive relapsing. While these descriptions of MS have become well-established, our understanding of MS and the course of the disease has advanced since that time, prompting a re-evaluation of the course of MS and any biological signposts (such as blood markers or imaging) that might help refine these definitions.

What did the reassessment recommend?
After a thorough search of the medical literature and convening an international workshop,* the Committee has now reviewed advances in what we know and don’t yet know in terms of identifying different types of MS in individuals, and has made recommendations that modify prior clinical course descriptions. In the resulting paper, the Committee recommended retaining much of what we consider the courses of MS – relapsing-remitting, secondary-progressive and primary progressive, but has recommended categorizing progressive relapsing as an active form of primary progressive MS.

Importantly, they recommended that clinicians not just determine a person’s course of MS, but further sub-categorize that course as “active” or “not active” (depending on the presence of clinical relapses or activity on MRI scans) or as progressing (worsening) or not progressing, based on clinical evidence of changes in disability. This, the Committee believes, provides a truer picture of what an individual experiences, can better inform treatment decisions, and refine clinical trial design and recruitment.

What Does This Mean for People with MS?
Ultimately these recommendations will advance better care for people with MS by:
• raising awareness that people with all forms of MS should be monitored for signs of disease activity and progression, which may open up additional treatment options;
• improving outcomes of clinical trials, which could bring new therapies faster.

What Additional Research is Needed?
The Committee pointed out areas for further needed research to help find additional solutions to the unpredictable nature of MS, including:
• Long-term studies that track people affected by MS over time;
• Assessing whether the degree of recovery from relapses has an impact on long-term outcomes;
• Imaging studies of tissue damage and its relation to disease course;
• Advanced imaging techniques such as those that measure brain atrophy or optic nerve thinning;
• Studying large datasets for fluid-borne biomarkers to better asses their ability to help define clinical phenotypes;
• Incorporating information reported by people who have the disease (“patient-reported outcomes”) in refining the courses of MS.

Researchers funded by the National MS Society and others worldwide are already working toward these goals, in efforts to help people with MS live their best lives. In addition, this information will be considered by the Society’s leadership as it develops future research strategies.

Read more about research we fund.

*Workshop supported by the National MS Society, ECTRIMS, the Americas Committee for Treatment and Research in MS, the MS International Federation, and the MS Society of Canada.

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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