Clinical Study to Evaluate the Efficacy, Safety, and Tolerability of ACT-128800 in Patients With Relapsing-remitting Multiple Sclerosis

Inclusion Criteria:

Adult males and females
Diagnosis of RRMS as defined by the revised (2005) McDonald Diagnostic Criteria for Multiple Sclerosis (MS).
Signed inform consent prior to initiation of any study-mandated procedure.

Exclusion Criteria:

A diagnosis of MS categorized as primary progressive or secondary progressive or progressive relapsing.
Patients currently treated for an autoimmune disorder other than MS.
Contraindications for MRI.
Ongoing bacterial, viral, or fungal infection.
History or presence of malignancy.

Additional inclusion and exclusion criteria apply with respect to medical conditions and concomitant treatments which could affect patients' risk from participating in the study.