Efficacy and Safety of BIIB019 (Daclizumab High Yield Process) Versus Interferon β 1a in Participants With Relapsing-Remitting Multiple Sclerosis

Key Inclusion Criteria:

Must have a confirmed diagnosis of Relapsing Remitting Multiple Sclerosis (RRMS), and a cranial magnetic resonance imaging (MRI) demonstrating lesion(s) consistent with MS
Must have a baseline Expanded Disability Status Scale (EDSS) between 0.0 and 5.0, inclusive
Male subjects and female subjects of childbearing potential must be willing to practice effective contraception during the study and be willing and able to continue contraception for 4 months after their last dose of study treatment

Key Exclusion Criteria:

Known intolerance, contraindication to, or history of non-compliance with Avonex® 30 µg
History of treatment with Daclizumab High Yield Process (Dac HYP)
History of malignancy
History of severe allergic or anaphylactic reactions
Known hypersensitivity to study drugs or their excipients
History of abnormal laboratory results indicative of any significant disease
History of human immunodeficiency virus (HIV) or other immunodeficient conditions
History of drug or alcohol abuse (as defined by the Investigator) within the 2 years prior to randomization
History of seizure disorder or unexplained blackouts OR history of a seizure within 6 months prior to Baseline
History of suicidal ideation or an episode of clinically severe depression (as determined by the Investigator) within 3 months prior to Day 1
An MS relapse that has occurred within the 50 days prior to randomization AND/OR the subject has not stabilized from a previous relapse prior to randomization
Known history of, or positive screening test result for hepatitis C virus or hepatitis B virus
Varicella or herpes zoster virus infection or any severe viral infection within 6 weeks before screening
Exposure to varicella zoster virus within 21 days before screening

NOTE: Other protocol-defined Inclusion/Exclusion criteria may apply.