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Open-Label Natalizumab Safety Extension Study

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: January 13, 2006
Last Update Posted: June 22, 2009
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
The primary objective of this study is to determine the safety and the immunogenicity of extended treatment with natalizumab when administered at a dose of 300 mg intravenously (IV) to subjects with multiple sclerosis (MS) who have completed natalizumab Studies C-1801, C-1802, or C-1803.

Condition Intervention Phase
Multiple Sclerosis Drug: Natalizumab Phase 3

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: An Open-Label, Multicenter Extension Study to Evaluate the Safety and Tolerability of Natalizumab in Subjects With Multiple Sclerosis Who Have Completed Studies C-1801, C-1802, or C-1803

Resource links provided by NLM:

Further study details as provided by Biogen:

Primary Outcome Measures:
  • The safety endpoints under consideration will be the incidence of adverse events, changes in laboratory evaluations, vital signs, and physical examinations. The incidence of development of antibodies to natalizumab will also be assessed. [ Time Frame: Month 24 ]

Secondary Outcome Measures:
  • EDSS scores and assessments of relapse. [ Time Frame: Month 24 ]

Enrollment: 1615
Study Start Date: December 2003
Study Completion Date: January 2006
Primary Completion Date: October 2005 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Natalizumab
Open-label natalizumab
Drug: Natalizumab
Natalizumab 300 mg by IV infusion, every 4 weeks, for up to 24 months
Other Name: Tysabri


Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Must give written informed consent.
  • Must be an MS subject who has completed natalizumab Study C-1801, C-1802 or C-1803

Exclusion Criteria:

  • History of, or available abnormal laboratory results, indicative of any significant disease that would preclude treatment.
  • History of severe allergic or anaphylactic reactions or known drug hypersensitivity
  • A clinically significant infectious illness within 30 days prior to study entry.
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00276172

United States, Massachusetts
Performed at only C-1801, C-1802, and C-1803 sites globally. No general public enrollment. Biogen Idec is located in
Cambridge, Massachusetts, United States, 02142
Sponsors and Collaborators
Study Director: Michael Panzara, MD, MPH Biogen
Principal Investigator: Paul O'Connor, MD St. Michael's Hospital, Toronto
Study Chair: Eve Versage Biogen Idec. Contact for more details
  More Information

Responsible Party: Biogen Idec MD, Biogen Idec
ClinicalTrials.gov Identifier: NCT00276172     History of Changes
Other Study ID Numbers: C-1808
First Submitted: January 11, 2006
First Posted: January 13, 2006
Last Update Posted: June 22, 2009
Last Verified: June 2009

Additional relevant MeSH terms:
Multiple Sclerosis
Pathologic Processes
Demyelinating Autoimmune Diseases, CNS
Autoimmune Diseases of the Nervous System
Nervous System Diseases
Demyelinating Diseases
Autoimmune Diseases
Immune System Diseases
Immunologic Factors
Physiological Effects of Drugs