Disease Control and Safety in Patients With Relapsing Remitting Multiple Sclerosis (RRMS) Switching From Natalizumab to Fingolimod

Patient were screened, signed an informed consent at visit 1, at the 2nd visit, all patient received a baseline infusion of Natalizumub and subsequently randomized to one of 3 treatment arms. At the randomization visit, the Washout Phase started, and eligible patients were randomized 1:1:1 to one of three treatment groups: * 8-week washout (8 weeks no treatment) followed by 24 weeks of treatment with fingolimod, * 12-week washout (8 weeks no treatment and 4 weeks placebo) followed by 20 weeks of treatment with fingolimod, or * 16-week washout (8 weeks no treatment and 8 weeks placebo) followed by 16 weeks of treatment with fingolimod.