This study used a 2-cohort, nonrandomized, open-label, multicenter design. Cohort 1: The first cohort was to be comprised of approximately 200 patients with RMS, who were newly prescribed commercially available fingolimod 0.5 mg/day. Cohort 2: The second cohort was to be comprised of approximately 200 RMS patients who had been on commercially available fingolimod 0.5 mg/day continuously without interruption of treatment for at least ≥ 2 years. Patients from both cohorts were recruited simultaneously from up to 125 MS centers in the United States. Both cohorts ran concurrently. The study consisted of 2 periods: Screening (up to 4 weeks) and Treatment period from Baseline (end of screening period considered as Day 1) up to 12 months with visits conducted at 3,6 and 12 months with a 14 day follow-up post treatment..
