Natalizumab (Tysabri) Re-Initiation of Dosing

Study Overview
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Brief Summary
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The primary objectives for the initial treatment period of this study are to further evaluate the safety of natalizumab monotherapy by evaluating the risk of hypersensitivity reactions and immunogenicity following re-exposure to natalizumab and confirming the safety of switching from interferon (IFN), glatiramer acetate, or other multiple sclerosis (MS) therapies to natalizumab. The primary objective for the long-term treatment period of this study is to evaluate the long-term impact of natalizumab monotherapy on the progression of disability measured by Expanded Disability Status Scale (EDSS) changes over time.

Detailed Description
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Study 101-MS-322 (NCT00306592) was conducted to evaluate the safety of natalizumab monotherapy following re-exposure to natalizumab in former clinical trial participants in Studies C-1801 (NCT00027300), C-1802 (NCT00030966), and C-1803 (NCT00097760) and included subjects in North America. In parallel with the conduct of that study, this study (101-MS-321 [NCT00297232]) was initiated for participants in Europe and the rest of the world. In addition, after 48 weeks, participants from 101-MS-322 (NCT00306592) could enter study 101-MS-321 (NCT 00297232), which was considered the Long-Term Treatment Period of 101-MS-322 (NCT00306592). The primary purpose and primary outcome for both studies are identical; therefore, the combined long-term data from both studies are presented. (Combined Week 48 data from both studies are presented in the 101-MS-322 [NCT00306592] record.)

Official Title
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An Open-Label, Multicenter, Extension Study to Evaluate the Safety and Tolerability of Natalizumab Following Re-Initiation of Dosing in Multiple Sclerosis Subjects Who Have Completed Study C-1801, C-1802, C-1803, or C-1808 and a Dosing Suspension Safety Evaluation

Conditions
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Relapsing-Remitting Multiple Sclerosis

Intervention / Treatment
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* Drug: Natalizumab


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria MS subjects who completed Study C-1801 (NCT00027300), C-1802 (NCT00030966), or C-1803 (NCT00097760) and a Dosing Suspension Safety Evaluation (neurological examination or a magnetic resonance imaging scan) or participated in the IMA 04001 (STARS) Study Subjects who are considered by the Investigator to be free of signs and symptoms suggestive of progressive multifocal leukoencephalopathy and willing to discontinue and remain free from concomitant immunosuppressive or immunomodulatory treatment (including IFN-beta and glatiramer acetate) while being treated with natalizumab during the study. In addition, subjects who completed 48 weeks of treatment in Study 101-MS-322 (NCT00306592) in Canada will be allowed to enter this study at the start of the long-term treatment period (Week 52 - 480). Key Exclusion Criteria Considered by the Investigator to be immunocompromised History of persistent anti-natalizumab antibodies, based upon testing from prior natalizumab studies History of any major disease or malignancy Discontinued natalizumab in a previous study due to allergic reaction NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Natalizumab<br>300 mg intravenous (IV) infusions once every 4 weeks for up to 480 weeks | Drug: Natalizumab<br> <br> * Other names: Tysabri (BG00002);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to 24-week Confirmed Expanded Disability Status Scale (EDSS) Progression | Time to 24-week confirmed EDSS progression in participants with at least 2 post-baseline milestone EDSS assessments. EDSS assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was reported. Confirmed 24-week EDSS progression was defined as ≥ 0.5 point increase from a baseline EDSS ≥ 6.0, or ≥ 1.0 point increase from a baseline EDSS ≥ 1.0 and < 6.0, or ≥ 1.5 point increase from a baseline EDSS of 0, all sustained for 24 weeks. | up to 480 weeks | 
| Time to 48-week Confirmed EDSS Progression | Time to 48-week confirmed EDSS progression in particpants with at least 2 post-baseline milestone EDSS assessments. EDSS assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was reported. Confirmed 48-week EDSS progression was defined as ≥ 0.5 point increase from a baseline EDSS ≥ 6.0, or ≥ 1.0 point increase from a baseline EDSS ≥ 1.0 and < 6.0, or ≥ 1.5 point increase from a baseline EDSS of 0, all sustained for 48 weeks. | up to 480 weeks | 
| Time to 24-week Confirmed EDSS Improvement Where Baseline ≥ 2.0 | Time to 24-week confirmed EDSS improvement in subjects with at least 2 post-baseline milestone EDSS assessments. EDSS assesses disability in 8 functional systems. An overall score ranging from 0 (normal) to 10 (death due to MS) was reported. Confirmed 24-week EDSS improvement is defined as ≥ 1.0 point decrease from baseline sustained for 24 weeks. | Up to 480 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Multiple Sclerosis, MS