Exploratory Study of the Safety, Tolerability and Efficacy of Multiple Regimens of Natalizumab in Adult Participants With Relapsing Multiple Sclerosis (MS)

Study Overview
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Brief Summary
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The primary objective of this study is to explore the effects of multiple regimens of natalizumab on disease activity and safety in participants with relapsing-remitting Multiple Sclerosis (RRMS).

Detailed Description
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This is a a dose and frequency (but not route of administration) blinded, prospective, randomized, dose-ranging study in patients with RRMS who have received natalizumab for at least 12 months according to the local prescribing guidelines. The study will explore dosing of natalizumab by subcutaneous and intravenous routes. Participants will be randomly assigned to 1 of 6 dosing regimens, blinded to natalizumab dose, but not route, for 60 weeks of treatment.

Official Title
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A Randomized, Blinded, Parallel-Group, Phase 2 Study Exploring the Safety, Tolerability, and Efficacy of Multiple Regimens of Natalizumab in Adult Subjects With Relapsing Multiple Sclerosis

Conditions
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Relapsing-Remitting Multiple Sclerosis

Intervention / Treatment
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* Drug: natalizumab IV
* Drug: natalizumab SC
* Drug: IV Placebo
* Drug: SC Placebo


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Ability to provide written informed consent Subjects of childbearing potential must practice effective contraception during the study A documented diagnosis of Relapsing Remitting Multiple Sclerosis (RRMS) Free of MS relapse for 12 months prior to randomization Treatment with natalizumab for a minimum of 12 months immediately prior to randomization. In the 12 months prior to commencing natalizumab, subject must have experienced a minimal level of disease activity as defined by 2 or more documented clinical relapses OR 1 relapse and documented MRI activity, defined by the presence of at least 1 Gd enhancing lesion on MRI, unrelated to the relapse. Key Exclusion Criteria: Known history of Human Immunodeficiency Virus (HIV), hepatitis C and/or hepatitis B virus Positive for anti-natalizumab antibodies at screening MRI positive for Gd-enhancing lesions at study entry Subjects for whom MRI is contraindicated History of any clinically significant cardiac, endocrinologic, hematologic, hepatic, immunologic, metabolic (including diabetes), urologic, pulmonary, neurologic (except for RRMS), dermatologic, psychiatric, renal, or other major disease History of malignant disease, including solid tumors and hematologic malignancies (with the exception of cured basal cell and squamous cell carcinomas of the skin) History of transplantation or any anti-rejection therapy History of severe allergic or anaphylactic reactions or known hypersensitivity to any drug A clinically significant infectious illness within 30 days prior to screening or progressive multifocal leukoencephalopathy (PML) or other opportunistic infections at any time Signs or symptoms suggestive of any serious infection, based on medical history, physical examination or laboratory testing NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Natalizumab 300 mg Intravenous (IV) Every 4 Weeks<br>Natalizumab 300 mg IV every 4 weeks for 60 weeks. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;|
| Experimental: Natalizumab 300 mg Subcutaneous (SC) Every 4 Weeks<br>Natalizumab 300 mg SC every 4 weeks for 60 weeks. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;Drug: natalizumab SC<br>* natalizumab for Subcutaneous Injection<br>* Other names: BG00002;|
| Experimental: Natalizumab 300 mg IV Every 12 Weeks<br>Natalizumab 300 mg IV every 12 weeks for 60 weeks with matching IV placebo administered during the intervening 4-week periods. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;Drug: IV Placebo<br>* Intravenous placebo to natalizumab<br>|
| Experimental: Natalizumab 300 mg SC Every 12 Weeks<br>Natalizumab 300 mg SC every 12 weeks for 60 weeks with matching SC placebo administered during the intervening 4-week periods. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;Drug: natalizumab SC<br>* natalizumab for Subcutaneous Injection<br>* Other names: BG00002;Drug: SC Placebo<br>* Subcutaneous placebo to natalizumab<br>|
| Experimental: Natalizumab 150 mg IV Every 12 Weeks<br>Natalizumab 150 mg IV every 12 weeks for 60 weeks with matching IV placebo administered during the intervening 4-week periods. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;Drug: IV Placebo<br>* Intravenous placebo to natalizumab<br>|
| Experimental: Natalizumab 150 mg SC Every 12 Weeks<br>Natalizumab 150 mg SC every 12 weeks for 60 weeks with matching SC placebo administered during the intervening 4-week periods. Open-label natalizumab treatment 300 mg IV at Weeks 60, 64, and 68. | Drug: natalizumab IV<br>* natalizumab for IV Infusion<br>* Other names: BG00002;Drug: natalizumab SC<br>* natalizumab for Subcutaneous Injection<br>* Other names: BG00002;Drug: SC Placebo<br>* Subcutaneous placebo to natalizumab<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cumulative Number of Combined Unique Active Lesions | Cumulative number of combined unique active lesions (sum of the number of new gadolinium (Gd)-enhancing lesions and new or newly enlarging T2 hyperintense lesions not associated with Gd-enhancement on T1 weighted scans) based on brain magnetic resonance imaging (MRI) scans Up to Week 60. | Up to Week 60 |