Conditions: Multiple Sclerosis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 106
Healthy volunteers: no

Brief summary:
The primary objective of Part A is to determine the safety and tolerability of natalizumab administered over 24 weeks in Japanese participants with relapsing-remitting multiple sclerosis (MS). The endpoints for this will include assessment of adverse evetns (AEs), changes in laboratory evaluations, vital signs, Expanded Disability Status Scale (EDSS) scores, and changes in physical and neurological examination findings. The secondary objectives of Part A are to characterize the pharmacokinetics (PK) profile and pharmacodynamics (PD) of natalizumab.

The primary objective of Part B is to determine if natalizumab, when compared to placebo, is effective in treating Japanese participants with relapsing-remitting MS, as measured by new active lesions on cranial magnetic resonance imaging (MRI) scans over 24 weeks. New active lesions are the sum of the gadolinium-enhancing (Gd+) lesions and any new or newly-enlarging T2-hyperintense lesions that do not enhance. The primary endpoint is the rate of development of new active lesions over 24 weeks.

Secondary objectives of Part B are to determine over 24 weeks whether natalizumab, when compared to placebo, is effective in reducing the frequency of clinical exacerbations, reducing the number of Gd+ lesions, reducing the number of new or newly-enlarging T2-hyperintense lesions on brain MRI scans, increasing the proportion of relapse-free participants, and improving outcomes on visual analog scale (VAS) assessing the participant's global impression of his/her well-being. Additional objectives are to assess the safety and tolerability, the incidence of serum antibodies to natalizumab and the PK profile of natalizumab.

Detailed description:
This multicenter study has 2 parts and is designed to provide data in Japanese participants, as required for registration of natalizumab (BG00002) in Japan. Part A will consist of an open-label cohort of 12 participants who will receive 300 mg natalizumab intravenously (IV) every 4 weeks over a 6-month treatment period. Part B will consist of a double-blind, placebo-controlled cohort of approximately 90 participants randomized in a ratio of 1:1 to receive IV infusions of placebo or 300 mg BG00002 every 4 weeks over a 6-month period.

Arms:
arm 1: 300 mg IV infusions of natalizumab over 60 minutes every 4 weeks for 20 weeks arm 2: IV infusions of placebo over 60 minutes every 4 weeks for 20 weeks arm 3: 300 mg IV infusions of natalizumab over 60 minutes every 4 weeks for 20 weeks

Interventions: intervention 1: Natalizumab (BG00002) intervention 2: Placebo
Intervention descriptions: intervention 1: None intervention 2: None

Protocol document: