An observational study in Multiple Sclerosis, Relapsing-Remitting, sponsored by Kessler Foundation. Completed at 1 site in United States. Open to participants aged 18 Years to 64 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by Kessler Foundation · Observational
The purpose of this research study is to investigate the effectiveness of Tysabri on cognitive fatigue in persons with Relapsing-Remitting Multiple Sclerosis (RRMS). Cognitive fatigue is the kind of fatigue that occurs after intense mental concentration as after a session of problem solving.
The researchers aim is to investigate the effects of Tysabri on cognitive fatigue and on specific brain areas that have been shown to underlie cognitive fatigue in individuals with RRMS. The researchers will investigate the effects on the cognitive fatigue that develops during the performance of a demanding task and also on how cognitive fatigue changes as a function of duration of treatment.
602 studies on the registry are indexed under Multiple Sclerosis, Relapsing-Remitting; 80 are open to participants now.
This study's enrollment of 7 is below the median of 116 across 151 observational studies indexed under Multiple Sclerosis, Relapsing-Remitting.
Browse Multiple Sclerosis, Relapsing-Remitting studies →Kessler Foundation is the lead sponsor of 170 studies on the registry; 58 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Individuals diagnosed with Relapsing-Remitting Multiple Sclerosis and Healthy Volunteers
Exclusion Criteria:
Individuals with RRMS who are going to be starting Tysabri as determined by Neurologist as part of clinical care. Intervention: Drug: Tysabri
Drug: Tysabri
Healthy individuals who are age, gender and education matched to the MS group.
Participants with RRMS who are planning to begin treatment with Tysabri will be compared to a group of healthy individuals who are matched for age, gender, and education.
Brain activation (BOLD signal)
A change in brain activation as measured with functional magnetic resonance imaging through blood oxygen level dependent signal will be measured in association with cognitive fatigue (as measured by the Visual Analogue scale during performance of the modified Symbol Digit Modality Task and Modified Fatigue Impact Scale).
Time frame: Measured by change between 2 time points (baseline and six months after intervention)
Fatigue onset (SDMT)
A change in the speed with which modified Symbol Digit Modality Task (a cognitively demanding task) induces fatigue in MS (as measured by the Visual Analogue scale)
Time frame: Measured by change between 2 time points (baseline and six months after intervention)
Fatigue onset
A change in brain activation as measured with functional magnetic resonance imaging through blood oxygen level dependent signal will be measured in association with cognitive fatigue (as measured by the Modified Fatigue Impact Scale)
Time frame: Measured by change between 2 time points (baseline and six months after intervention)
This study is completed, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Multiple Sclerosis, Relapsing-Remitting→
Kessler Foundation