Long-Term Assessment of Remyelinating Therapy

The primary objective of the study is to assess full-field visual evoked potential (FF-VEP) latency in subjects who were enrolled in Study NCT01721161 2 years (+ up to 12 months) after the last study visit. The secondary objective is to assess clinical progression and severity of central nervous system (CNS) demyelinating disease in subjects who were enrolled in Study NCT01721161 2 years (+ up to 12 months) after the last study visit. Intervention was administered in the previous study. The participants, investigator and outcome assessors remain blinded in this follow-up study.