- Alping P, et al. Effectiveness of initial MS Treatments in the COMBAT-MS Trial: Injectables, Dimethyl Fumarate, Natalizumab, and Rituximab. OP34, ECTRIMS 2021 Virtual Congress, 13–15 October. Copyright ©2021 Medicom Medical Publishers.
Direct comparisons of therapies provide valuable information for physicians treating MS patients. Therefore, the current real-world study investigated the effectiveness of the most frequently prescribed initial MS therapies in Sweden. MS patients, ever-treated with initial rituximab (n=472), natalizumab (n=269), dimethyl fumarate (n=339), or injectables (interferon- β, glatiramer acetate) (n=858), were followed between 2010 and 2020.
First relapse (time to event), MRI lesion rate, Expanded Disability Status Scale (EDSS) score, and treatment discontinuation (time to event) were the outcome measures of this study. Rituximab served as the reference therapy. The results were presented by Dr. Peter Alping (Karolinska Institute, Sweden). Initial treatment with injectables demonstrated the highest probability of relapse (HR 6.0) in this population, followed by dimethyl fumarate (HR 2.9) and natalizumab (HR 1.8).
However, baseline characteristics showed that natalizumab users were on average younger and had experienced the most relapses prior to the study onset. For that reason, the results should be interpreted with caution. Rate ratios of MRI lesions favoured initial rituximab therapy over injectables (rate ratio 4.5), dimethyl fumarate (4.8), and natalizumab (1.9). Interestingly, only injectables demonstrated significantly higher EDSS scores than rituximab.
Natalizumab and dimethyl fumarate showed similar EDSS scores to rituximab. The time to treatment discontinuation was the shortest for injectables, followed by dimethyl fumarate, and natalizumab. Patients who were initially treated with dimethyl fumarate or injectables discontinued mainly due to adverse events or an inadequate effect of the therapy. Natalizumab users frequently discontinued their therapy due to JC virus positivity and the fear of progressive multifocal leukoencephalopathy.