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Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells
Published on: December 13, 2016
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Magnetization transfer ratio in the delayed-release dimethyl fumarate DEFINE study.
Douglas L Arnold1, Ralf Gold, Ludwig Kappos
1NeuroRx Research, Montreal, QC, Canada, darnold@neurorx.com.
Journal of Neurology
|October 2, 2014
Summary
Delayed-release dimethyl fumarate (DMF) increased myelin density in patients with relapsing-remitting multiple sclerosis (RRMS). This suggests DMF may promote remyelination and cytoprotection, as indicated by magnetization transfer ratio (MTR) changes.
Area of Science:
- Neuroscience
- Radiology
Background:
- Relapsing-remitting multiple sclerosis (RRMS) is characterized by myelin damage.
- Magnetization transfer ratio (MTR) is a neuroimaging biomarker sensitive to myelin changes.
- Delayed-release dimethyl fumarate (DMF) is an oral therapy for RRMS.
Purpose of the Study:
- To evaluate the effect of delayed-release DMF on myelin density in RRMS patients.
- To assess changes in MTR as a biomarker of myelin integrity during DMF treatment.
Main Methods:
- Phase 3 DEFINE study: randomized, double-blind, placebo-controlled trial.
- 2-year treatment with delayed-release DMF (BID or TID) or placebo in RRMS patients.
- MTR analysis in whole brain and normal-appearing brain tissue (NABT) at multiple time points.
Main Results:
- Delayed-release DMF treatment led to significant increases in MTR in both whole brain and NABT.
- Placebo group showed a reduction in MTR, indicating myelin loss.
- Results were consistent in subgroups of patients with no new lesions or relapses.
Conclusions:
- Increases in MTR suggest that delayed-release DMF promotes myelin repair or increases myelin density in RRMS.
- Findings support the potential of delayed-release DMF for cytoprotection and remyelination in RRMS.
- MTR serves as a valuable biomarker for assessing therapeutic effects on myelin in MS.
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