BIIB033 In Acute Optic Neuritis (AON)

A Randomized, Double-Blind, Parallel-Group, Placebo Controlled Study to Assess the Efficacy, Safety, Tolerability, and Pharmacokinetics of BIIB033 in Subjects With First Episode of Acute Optic Neuritis

The primary objective of the study is to evaluate the efficacy of BIIB033 in subjects with their first episode of unilateral acute optic neuritis (AON). The secondary objective of this study is to assess the safety, tolerability, and pharmacokinetics (PK) of BIIB033 in this study population.

Key Inclusion Criteria:

• Ability to provide written consent and any authorization required by law.
• Confirmed diagnosis of AON
• All male or female subjects of childbearing potential must practice effective contraception during the study and be willing and able to continue contraception for at least 6 months after their last dose of study treatment.

Key Exclusion Criteria:

• Prior episode(s) of optic neuritis or loss of vision not due to AON.
• Subjects with an established diagnosis of multiple sclerosis are excluded except if newly diagnosed based on the current episode of AON and positive brain magnetic resonance imaging results consistent with the 2010 revisions to the McDonald's criteria.
• Previous history of a clinically significant disease.
• Females who have a positive pregnancy test result, or who are pregnant, breastfeeding, or planning to conceive during the study.
• History of human immunodeficiency virus (HIV), hepatitis C virus antibody, or hepatitis B virus.
• History or evidence of drug or alcohol abuse within 2 years prior to Screening.
• Current enrollment in any other study treatment or disease study within 3 months prior to Day 1/Baseline.

NOTE: Other protocol-defined inclusion/exclusion criteria may apply.