Multimodal MRI Response to Fingolimod in Multiple Sclerosis: A Nonrandomized, Single Arm, Observational Study

BACKGROUND AND PURPOSE Fingolimod has a favorable effect on conventional MRI measures; however, its neuroprotective effect is not clear. We aim to investigate changes of conventional and advanced MRI measures in lesions and normal-appearing white matter (NAWM) over 2 years in fingolimod-treated patients. METHODS Fifty relapsing-remitting multiple sclerosis patients and 27 healthy controls were enrolled in the study and underwent baseline, 1-year, and 2-year 3T MRI scans. T2 lesion volume, whole brain volume, cortical gray matter volume, white matter volume, corpus callosum area, percentage brain volume change (PBVC), Expanded Disability Status Scale, gadolinium-enhancing lesions, PBVC, magnetization transfer ratio (MTR), and diffusion tensor imaging metrics (fractional anisotropy [FA] and median diffusivity [MD]) in lesions and NAWM were calculated. Longitudinal changes were examined using one-way repeated measures ANOVA. Bonferroni correction for multiple testing was used when appropriate. RESULTS Conventional MRI measures were unchanged in both groups. Lesion MTR increased significantly (P < .001), but NAWM-MTR remained unchanged. Lesion FA improved significantly in year 1 (P = .003) and over the study duration (P = .05). Lesion MD changed significantly from baseline to year 1 (P < .001) and remained stable over 2 years. NAWM-FA was significant from baseline to year 1 (P = .002) and from baseline to year 2 (P < .001). NAWM-MD was significant only from baseline to year 1 (P = .001). CONCLUSIONS These findings suggest a possible neuroreparative effect of fingolimod on the MS lesions and NAWM. Larger and longer randomized studies are required to confirm these results.