To evaluate clinical perspectives of proton multi-voxel magnetic-resonance spectroscopy (PMMRS) for monitoring the severity of multiple sclerosis (MS) and neurodegenerative process, we studied the changes of the NAA/Cr ratio in the brain tissue of patients with MS and calculated the correlations between this parameter and the clinical state of patients. Based on these results, we studied the potential neuroprotective effect of β-interferon 1a (avonex) for intramuscular injection in patients with remitting MS. Twenty-six patients with remitting MS were enrolled in the study. The study of anamnesis, neurological examination using EDSS, neuropsychological testing and dynamic MRI using PMMRS were performed. The NAA/Cr ratio was decreased in patients compared to controls. An analysis of the NAA/Cr ratio after one year revealed the significant decrease of this parameter. The negative correlation between the NAA/Cr ratio in the brain tissue and the level of neurological and cognitive deficits was noted. The analysis of existing treatment of MS with β-interferon 1a for intramuscular injection revealed the neuroprotective stabilizing effect during one year of treatment that is probably associated with the effect of this drug on the neurodegenerative process in MS.