Inclusion Criteria:

• Diagnosis of MS and cranial MRI scan demonstrating white matter lesions attributable to MS within 5 years
• Onset of MS symptoms within 5 years
• EDSS score 0.0 to 3.0
• ≥2 MS attacks within 24 months, with ≥1 attack within 12 months

Exclusion Criteria:

• Received prior therapy for MS other than corticosteroids
• Exposure to immunosuppressive or immunomodulatory agents other than systemic corticosteroid treatment
• Received treatment with a monoclonal antibody for any reason
• Previous treatment with any investigational drug (i.e. medication that is not approved at any dose for any indication)
• Has any progressive form of MS
• Any disability acquired from trauma or another illness that could interfere with evaluation of disability due to MS
• Major systemic disease that cannot be treated or adequately controlled by therapy
• Active infection or high risk for infection
• Autoimmune disorder (other than MS)
• Impaired hepatic or renal function
• History of malignancy, except basal skin cell carcinoma
• Medical, psychiatric, cognitive, or other conditions that compromise the patient's ability to understand the patient information, to give informed consent, to comply with the trial protocol, or to complete the study
• Known bleeding disorder
• Of childbearing potential with a positive serum pregnancy test, pregnant or lactating
• Current participation in another clinical study
• Previous hypersensitivity reaction to any immunoglobulin product
• Known allergy or intolerance to interferon beta, human albumin, or mannitol
• Intolerance of pulsed corticosteroids, especially a history of steroid psychosis
• Inability to self-administer subcutaneous (SC) injections or receive SC injections from caregiver
• Inability to undergo MRI with gadolinium administration
• Unwilling to use a reliable and acceptable contraceptive method throughout the study period (fertile patients only)