Conditions: Multiple Sclerosis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 419
Healthy volunteers: no

Brief summary:
The primary objective of the study is to evaluate the efficacy of BIIB033 in participants with active relapsing multiple sclerosis (MS) when used concurrently with Avonex.

Secondary objectives of this study in this study population are to assess the safety, tolerability, and population pharmacokinetics of BIIB033 when used concurrently with Avonex.

Detailed description:

Arms:
arm 1: BIIB033 3 mg/kg once every 4 weeks intravenous (IV) infusion up to Week 72.

Avonex once-weekly intramuscular (IM) injection up to Week 84. arm 2: BIIB033 10 mg/kg once every 4 weeks IV infusion up to Week 72.

Avonex once-weekly IM injection up to Week 84. arm 3: BIIB033 30 mg/kg once every 4 weeks IV infusion up to Week 72.

Avonex once-weekly IM injection up to Week 84. arm 4: BIIB033 100 mg/kg once every 4 weeks IV infusion up to Week 72.

Avonex once-weekly IM injection up to Week 84. arm 5: Placebo once every 4 weeks IV infusion up to Week 72.

Avonex once-weekly IM injection up to Week 84.

Interventions: intervention 1: BIIB033 intervention 2: Placebo intervention 3: Avonex
Intervention descriptions: intervention 1: None intervention 2: None intervention 3: None

Protocol document: