Author Affiliations: Departments of Neurology and Biomedicine, University Hospital Basel, Basel, Switzerland.
Multiple sclerosis (MS) is a chronic disease of unknown etiology that involves the central nervous system and affects an estimated 2.0 million to 2.5 million people worldwide.1 The majority of—but not all—patients with MS develop severe disability 10 to 20 years after diagnosis.2,3 Several controlled therapeutic trials have consistently shown that immunomodulatory treatments, interferon beta and glatiramer acetate, can reduce relapse frequency, relapse-related progression of impairment and disability, and inflammatory activity as depicted by magnetic resonance imaging.4 The common but disputed assumption has been that these clinical and radiographic findings in studies limited to 2 to 3 years' duration translate into long-term benefits, with delay or prevention of long-term disability in patients typically seen in a neurological practice. This is particularly important for a disease with a mean duration of 30 or more years.5,6
Tobias Derfuss, Ludwig Kappos. Evaluating the Potential Benefit of Interferon Treatment in Multiple Sclerosis. JAMA. 2012;308(3):290–291. doi:10.1001/jama.2012.8327