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NCT03399981 · ClinicalTrials.gov registry record
Tysabri Observational Cohort Study - Multiple Sclerosis (MS) Registries
A clinical trial, sponsored by Biogen.
- Completed
- Registry status
- 80,327
- Enrollment target
NCT03399981: Completed study, sponsored by Biogen.
NCT03399981 is a clinical trial that has completed, run by Biogen. The registered enrollment target is 80,327 participants. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03399981 has completed, sponsored by Biogen.
- COMPLETED
- Registry status
- 80,327 participants
- Enrollment target
Study Summary
The primary purpose of this study is to estimate the incidence of progressive multifocal leukoencephalopathy (PML) among patients who switched to Tysabri from disease modifying therapies (DMTs), including newer DMTs (including fingolimod, dimethyl fumarate and teriflunomide) and the established DMTs (interferon beta and glatiramer acetate). Researchers will also look to estimate the incidence of other serious opportunistic infections among patients who switch to Tysabri from newer DMTs (including fingolimod, dimethyl fumarate and teriflunomide) and the established DMTs (interferon beta and glatiramer acetate)
Primary Outcome
Confirmed cases of PML must have one of the following: • Brain biopsy or brain from post mortem examination showing evidence of viral cytopathic changes on hematoxylin and eosin (H \& E) staining associated with either positive immunohistochemistry for SV40 or in-situ hybridization for John Cunningham Virus (JCV) deoxyribonucleic acid (DNA) OR All of the following criteria: • Cerebrospinal fluid (CSF) with evidence of JCV DNA, preferably by ultra-sensitive quantitative polymerase chain reacti
Interventions
- BIOLOGICAL Tysabri
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 80,327 participants |
| Start Date | 2017-06-01 |
| Est. Completion | 2023-12-31 |
What the finished NCT03399981 record still lists
NCT03399981 is an observational study that tracks outcomes without assigning an intervention. Its 80,327 participants enrollment target places it among the larger protocols in the corpus.
The record links to 0 conditions, and to 1 intervention - of which Tysabri is the first listed.
NCT03399981 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03399981 about?
NCT03399981 is a clinical study titled "Tysabri Observational Cohort Study - Multiple Sclerosis (MS) Registries". The primary purpose of this study is to estimate the incidence of progressive multifocal leukoencephalopathy (PML) among patients who switched to Tysabri from disease modifying therapies (DMTs), including newer DMTs (including fingolimod, dimethyl fumarate and teriflunomide) and the established DMTs...
What is the current status of trial NCT03399981?
This trial is currently completed. The enrollment target is 80,327 participants. The study started on 2017-06-01. Estimated completion is 2023-12-31.
What interventions are being tested in trial NCT03399981?
The interventions under investigation include: Tysabri (BIOLOGICAL).
Who is sponsoring clinical trial NCT03399981?
This trial is sponsored by Biogen, which has 334 total clinical trials registered on ClinicalTrials.gov.
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