Effect of switching from glatiramer acetate 20 mg/daily to glatiramer acetate 40 mg three times a week on gray and white matter pathology in subjects with relapsing multiple sclerosis: A longitudinal DTI study.

Abstract

BACKGROUND:

Glatiramer acetate (GA) 40 mg × 3/weekly was approved for the treatment of relapsing-remitting multiple sclerosis (RRMS). While the beneficial effect of GA 20 mg/daily in MS patients on non-conventional MRI measures has been demonstrated, the effect of GA 40 mg × 3/weekly at the microstructural tissue level has yet to be explored.

OBJECTIVE:

To investigate the effect of switching from GA 20 mg/daily to GA 40 mg × 3/weekly on the evolution of microstructural changes in the thalamus and normal appearing white matter (NAWM), using diffusion tensor imaging (DTI).

METHODS:

In this observational, longitudinal, cross-over, 34-month MRI study, we recruited 150 RRMS patients that underwent MRI 12-18 months before switching (pre-index), during the switch (index) and 12-18 months after switching (post-index) from GA 20 mg/daily to GA 40 mg × 3/weekly. Regional DTI metrics and tract-based spatial statistics (TBSS) analyses were performed. Mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD) and fractional anisotropy (FA) were measured in thalamus and NAWM.

RESULTS:

Regional DTI measures, measures of whole brain, white and gray matter, and thalamus volumes, as well as lesion volume, showed no significant changes. However, the voxel-wise TBSS analysis showed increased FA both in the NAWM and thalamus, as well as increased MD and AD in NAWM, and decreased RD in NAWM (p < .05). Areas of increased FA and MD as well as decreased RD in the NAWM, and increased AD both in the NAWM and thalamus were detected between index to post-index (p < .05).

CONCLUSIONS:

This study confirms a comparable effect of GA 40 mg × 3/weekly to GA 20 mg/daily on DTI measures over 34 months.

• Authors: Robert Zivadinov, Niels Bergsland, Jesper Hagemeier, Eleonora Tavazzi, Deepa P Ramasamy, Jackie Durfee, Mariya Cherneva, Ellen Carl, Jillian Carl, Channa Kolb, David Hojnacki, Bianca Weinstock-Guttman
• Journal: Journal of the neurological sciences (J Neurol Sci) Vol. 387 Pg. 152-156 (04 15 2018) ISSN: 1878-5883 [Electronic] Netherlands
• PMID: 29571854 (Publication Type: Journal Article, Observational Study)
• Copyright: Copyright © 2018 Elsevier B.V. All rights reserved.

Chemical References

• Glatiramer Acetate

Topics

• Adolescent
• Adult
• Aged
• Analysis of Variance
• Anisotropy
• Cross-Over Studies
• Diffusion Magnetic Resonance Imaging
• Disability Evaluation
• Dose-Response Relationship, Drug
• Female
• Glatiramer Acetate (therapeutic use)
• Gray Matter (diagnostic imaging, drug effects)
• Humans
• Image Processing, Computer-Assisted
• Longitudinal Studies
• Male
• Middle Aged
• Multiple Sclerosis, Relapsing-Remitting (diagnostic imaging, drug therapy)
• White Matter (diagnostic imaging, drug effects)
• Young Adult