 Multiple Sclerosis MS is an autoimmune and neurodegenerative disease in the central nervous system CNS, characterized by a complex pathogenesis and heterogeneous symptoms. The histopathological hallmark of the disease is sclerotic lesions. These inflammatory lesions manifests as disabling relapses, and the number of relapses in the first few years after disease onset is associated with progression of disability, with a higher number of relapses leading to a more rapid progression. In addition, diffuse neurodegeneration seems to occur early in the disease, and even though it is not always clinically evident it is associated with disease progression. A reduction in relapse rate and neurodegeneration early in the MS disease course may slow the progression of disabilities and can possibly reduce overall disease burden. For the individual person with MS pwMS a reduction in overall disease burden will often improve quality of life, and since MS is a lifelong disease this is of great interest. Preventing disability in pwMS is also highly relevant in a societal perspective, as it lowers the large costs associated with increased disability. As a consequence, the importance of early treatment have been emphasized. 