A Study to Learn About the Safety of BIIB091 and Its Effect on Brain Inflammation When Taken Alone or With Diroximel Fumarate (DRF) in Adults With Relapsing Forms of Multiple Sclerosis (MS)
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Phase
Phase 2
Status
Completed
Study type
Interventional
Design
Randomized · Quadruple · Treatment
Enrollment
127actual
Sites
77
Countries
Bulgaria, Czechia, Germany +7
Every value on this page is a field the sponsor filed with ClinicalTrials.gov, reproduced. Dates are their own estimates, revised as a study runs, unless the registry marks them actual. sources →
Source: ClinicalTrials.gov, retrieved 2026-08-19
Dates
each axis at the precision it was filed, with the registry's own basis| Date | Filed | Basis | What it is |
|---|---|---|---|
| Start | 2023-07-25 | actual | When the study began enrolling |
| Primary completion | 2026-02-10 | actual | The date the last participant is measured for the primary outcome — the readout window |
| Study completion | 2026-02-10 | actual | The whole study's end, after follow-up |
| First posted | 2023-04-04 | actual | When this record first appeared on the registry |
| Results posted | — | When the sponsor posted results to the registry | |
| Record updated | 2026-02-20 | actual | The sponsor's own last edit to this record — every projection above is as current as this date |
What it studies
Condition
- Relapsing Forms of Multiple Sclerosis
Interventions
- Drug: BIIB091
- Drug: DRF
- Drug: Placebo
Primary outcomes
what the primary-completion date above is the date OFPart 1: Number of Participants With Adverse Events (AEs)
measured Day 1 up to Week 50
Part 1: Number of Participants With Serious Adverse Events (SAEs)
measured From signing the informed consent form (ICF) to Week 50
Part 2: Cumulative Number of New T1 Gadolinium-Enhancing (GdE) Lesions
measured Week 8 to Week 16
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