The Effect of Glatiramer Acetate on Retinal Nerve Fiber Layer Thickness in Patients with Relapsing–Remitting Multiple Sclerosis: A Longitudinal Optical Coherence Tomography Study
Optical coherence tomography (OCT) is a technique that allows for the assessment of retinal nerve fiber layer thickness (RNFLT) and total macular volume (TMV), which reflect neuroaxonal integrity within the retina. As such it has been used in multiple sclerosis (MS) to study neurodegeneration. Glatiramer acetate (GA) is a widely used treatment for MS, which is suggested to have a possible neuroprotective role.
The aim of this study was to assess RFNLT and TMV changes in relapsing–remitting MS (RRMS) patients who started treatment with GA and were followed for a 24-month period.
A cohort of 60 RRMS patients and 40 healthy controls (HCs) were imaged with OCT at baseline and follow-up. All subjects also underwent clinical and neurological examination. Measurements were compared between the RRMS patients and HCs as well as between optic neuritis (ON)-affected and ON-unaffected eyes.
At baseline, MS patients showed lower average RNFLT (p = 0.046) and TMV (p = 0.013) when compared with HCs. No significant differences in the evolution of OCT measures were detected over the follow-up between MS patients and HCs. MS patients with both affected and unaffected eyes showed significantly lower average RNFLT, temporal inferior RNFLT, and TMV at baseline, compared with HCs. No significant differences between ON-affected and ON-unaffected eyes in MS patients were detected over the follow-up, except for the nasal superior RNFLT (p = 0.019).
This study suggests a beneficial role of GA on retinal axonal degeneration in MS, and further confirms the utility of OCT to monitor the neuroprotective effect of disease-modifying treatment.
We acknowledge the contribution of Dejan Jakimovski for the technical part of the OCT protocol.
Compliance with Ethical Standards
This study was supported by an investigator-initiated grant from Teva Pharmaceuticals, Inc.
Conflict of interest
Robert Zivadinov received personal compensation from EMD Serono, Genzyme-Sanofi, Claret Medical, Celgene, and Novartis for speaking and consultant fees. He received financial support for research activities from Teva Pharmaceuticals, Biogen, Genzyme-Sanofi, Novartis, Claret Medical, Intekrin-Coherus, Protembis, and IMS Health. Eleonora Tavazzi, Jesper Hagemeier, and Ellen Carl have nothing to disclose. Channa Kolb has received speaker honoraria and consultant fees from EMD Serono, Teva Pharmaceuticals, Acorda, Novartis, Genzyme, and Biogen-Idec. David Hojnacki has received speaker honoraria and consultant fees from Biogen-Idec, Teva Pharmaceutical Industries Ltd., EMD Serono, Pfizer Inc., and Novartis. Bianca Weinstock- Guttman received honoraria as a speaker and as a consultant for Biogen Idec, Teva Pharmaceuticals, EMD Serono, Sanofi Genzyme, Novartis, and Acorda. Dr Weinstock-Guttman received research funds from Biogen Idec, Teva Pharmaceuticals, EMD Serono, Sanofi Genzyme, Novartis, and Acorda.
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