To compare infection-related hospitalizations, antibiotic prescriptions, and relapse rates among people with MS treated with rituximab or ocrelizumab.
Approach:
Study Design: Nationwide cohort study using Swedish administrative health registers and the Swedish MS Registry.
Participants: Included all patients recorded in the Swedish MS register starting any DMT between January 1, 2014 and December 31, 2024.
Infection Definitions: Three definitions of infections were used: serious infections (hospitalization), any recorded infection diagnosis, and any filled antibiotic prescription.
Statistical Analysis: Hazard ratios (HRs) estimated using univariable and multivariable Cox regression.
Key Findings:
Crude rate of serious infections was 22 per 1,000 person-years on rituximab and 30 on ocrelizumab.
Antibiotic use was increased by 26% on rituximab and 73% on ocrelizumab.
Relapse rate was substantially lower on ocrelizumab compared to rituximab.
Interpretation:
Ocrelizumab is associated with a higher rate of serious infections compared to rituximab.
Limitations:
The study is observational and may be subject to confounding factors.
Data is limited to Swedish health registers, which may not be generalizable to other populations.
