An observational study in Multiple Sclerosis, sponsored by Biogen. Completed at 15 sites in Czechia. Per ClinicalTrials.gov, last updated 2025-05-13.
Sponsored by Biogen · Observational
Among 127 studies in Multiple Sclerosis by Biogen — 2 open to participants now, 5 under way, 1 of them phase 3. Multiple Sclerosis · Biogen.
Among the 127 studies in Multiple Sclerosis by Biogen, this one is the 18th largest by enrollment of the 48 observational ones, is one of 4 that started in 2019, is one of 40 observational ones, and was the 119th registered.
3,264 studies on the registry are indexed under Multiple Sclerosis; 659 are open to participants now.
This study's enrollment of 675 is above the median of 100 across 970 observational studies indexed under Multiple Sclerosis.
Browse Multiple Sclerosis studies →2 of the 127 studies in Multiple Sclerosis by Biogen are open now, in 7 countries. Each count lists the studies.
Of the 430 Multiple Sclerosis studies recruiting now, 163 (38%) set no upper age limit and 211 (49%) stop at 75 or younger; 40 take children under 18; 96 take healthy volunteers.
This study: all sexes · no healthy volunteers.
The full table on the hub →127 studies; the count open now beside each. This study's row is marked.
First in 1999; this study’s year is marked. 4 started in 2019.
Median enrollment 110 across the 79 interventional studies, 380 across the 48 observational. Of the 118 that completed or were terminated, 36 (31%) have results posted.
Biogen is the lead sponsor of 511 studies on the registry; 24 are open to participants now.
Of its 100 completed or terminated interventional studies of FDA-regulated products, 50 (50%) have results posted.
None of the studies under way reaches primary completion within a year.
Among the 127 studies in Multiple Sclerosis by Biogen, from their registry updates:
Nothing recorded among them since 2026-09-25.
The primary objective of the study is to estimate the incidence of progressive multifocal leukoencephalopathy (PML) and serious adverse events (SAEs) of other opportunistic infections (OIs) among all participants taking natalizumab. The secondary objectives of the study are to estimate the incidence of SAEs, to estimate the incidence of SAEs among participant subgroups defined by demographic and clinical factors (age, gender, duration of treatment, pregnancy, breastfeeding), to characterize and estimate incidences of malignancies, hypersensitivity reactions and John Cunningham Virus (JCV) positivity among all participants taking natalizumab, and to count and describe pregnancies and breastfeeding among participants previously exposed to natalizumab.
The study will include participants with MS who are treated with natalizumab from the 1st of January 2019 and participating in the Czech National MS registry (ReMuS).
Key Inclusion Criteria:
Key Exclusion Criteria:
NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.
The cohort will include participants with MS who are newly treated with natalizumab (administered as a standard of care/routine clinical practice) from 1st January 2019 including those participants who terminate or discontinue the treatment during the observational period.
Drug: Natalizumab
Administered as specified in the treatment arm.
Also known as: Tysabri
Number of Participants With Progressive Multifocal Leukoencephalopathy (PML) who are Taking Natalizumab
Time frame: Up to 6 years
Number of Participants with Serious Adverse Events (SAEs) of Other Opportunistic Infections (OIs) who are Taking Natalizumab
SAE means such adverse event that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in permanent or significant damage to health or limitation of capabilities or is manifested as a congenital anomaly or birth defect in offspring, irrespective of the administered dose of the medicinal product. Serious OI means such OI which results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in permanent or significant damage to health or limitation of capabilities or is manifested as a birth defect in offspring.
Time frame: Up to 6 years
Number of Participants With SAEs
SAE means such adverse event that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in permanent or significant damage to health or limitation of capabilities or is manifested as a congenital anomaly or birth defect in offspring, irrespective of the administered dose of the medicinal product.
Time frame: Up to 6 years
Number of Participants With SAEs Among Participant Subgroups Defined by Demographic and Clinical Factors
SAE means such adverse event that results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in permanent or significant damage to health or limitation of capabilities or is manifested as a congenital anomaly or birth defect in offspring, irrespective of the administered dose of the medicinal product. Demographic and clinical factors involve age, gender, duration of treatment, pregnancy, breastfeeding.
Time frame: Up to 6 years
Number of Participants With Malignancies who are Taking Natalizumab
Time frame: Up to 6 years
Number of Participants With Hypersensitivity Reactions who are Taking Natalizumab
Time frame: Up to 6 years
Number of Participants who are John Cunningham Virus (JCV) Positive and Taking Natalizumab
Time frame: Up to 6 years
Number of Pregnant and Breastfeeding Participants who Were Previously Exposed to Natalizumab
Time frame: Up to 6 years
Plan to share: Yes — In accordance with Biogen's Clinical Trial Transparency and Data Sharing Policy on https://www.biogentrialtransparency.com/
Data sharing details ↗ · vivli.org
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This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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