Efficacy of rituximab in secondary progressive multiple sclerosis: Insights from magnetic resonance imaging and disability assessments.

Background: Although there are a few options for the treatment of patients with secondary progressive multiple sclerosis (SPMS), rituximab (RTX) is used as an off-label treatment. This study aimed to investigate the efficacy of RTX on disability status and volumetric magnetic resonance imaging (MRI) findings in SPMS.

Materials and methods: This study was conducted on 31 patients with SPMS treated with RTX 1000 mg intravenously every 6 months. Expanded Disability Status Scale (EDSS), 25-Foot Walk Test (25-FWT), 9-Hole Peg Test (9-HPT), and brain MRI were performed at the baseline and after 12 months.

Results: No significant changes were observed in EDSS, timed 25-FWT, and 9-HPT within 12 months of RTX treatment (P > 0.05). There was a decrease in 9-HPT time in both the right and left hands, but it was not significant. During the 12-month assessment, white matter (WM) and gray matter volumes decreased by -41.48 ± 2.36 and -31.65 ± 8.84, respectively. However, these differences were not statistically significant (P > 0.05). The only significant change was an increase in the volume of deep WM lesions (WMLs) (0.26 ± 0.19 vs. 0.38 ± 0.29, P = 0.024). A significant association was found between the EDSS at the 12^th month and baseline deep WML volume (r = 0.383, P = 0.044).

Conclusion: Our results showed that the level of disability based on EDSS, timed 25-FWT, and 9-HPT did not increase significantly during 12 months of treatment with RTX. These findings suggest that RTX may play a role in disease stabilization and preventing disability progression, especially in the upper limbs. Further studies with larger sample sizes are necessary to confirm this finding.