Abstract
Importance In patients with multiple sclerosis (MS), factors associated with severe COVID-19 include anti-CD20 therapies and neurologic disability, but it is still unclear whether these 2 variables are independently associated with severe COVID-19 or whether the association depends on MS clinical course. Objective To assess the association between anti-CD20 therapies and COVID-19 severity in patients with relapsing-remitting MS (RRMS) and progressive MS (PMS). Design, Setting, and Participants This multicenter, retrospective cohort study used data from the COVISEP study, which included patients with MS and COVID-19 from February 1, 2020, to June 30, 2022, at 46 French MS expert centers, general hospitals, and private neurology practices. Eligible patients with RRMS were those treated with high-efficacy MS therapy (ie, anti-CD20, fingolimod, or natalizumab), and eligible patients with PMS were those younger than 70 years with an Expanded Disability Status Scale (EDSS) score of 8 or lower. Patients were monitored from COVID-19 symptom onset until recovery or death. Exposures Current anti-CD20 therapy (ocrelizumab or rituximab). Main Outcomes and Measures The main outcome was severe COVID-19 (ie, hospitalization with any mode of oxygenation or death). All analyses were conducted separately in patients with RRMS and PMS using propensity score–weighted logistic regression. Subgroup analyses were performed according to COVID-19 vaccine status, sex, EDSS score, and age. Results A total of 1400 patients, 971 with RRMS (median age, 39.14 years [IQR, 31.38-46.80 years]; 737 [76.1%] female) and 429 with PMS (median age, 54.21 years [IQR, 48.42-60.14 years]; 250 [58.3%] female) were included in the study. A total of 418 patients with RRMS (43.0%) and 226 with PMS (52.7%) were treated with anti-CD20 therapies. In weighted analysis, 13.4% and 2.9% of patients with RRMS treated and not treated with anti-CD20 had severe COVID-19, respectively, and anti-CD20 treatment was associated with increased risk of severe COVID-19 (odds ratio [OR], 5.20; 95% CI, 2.78-9.71); this association persisted among vaccinated patients (7.0% vs 0.9%; OR, 8.85; 95% CI, 1.26-62.12). Among patients with PMS, 19.0% and 15.5% of patients treated and not treated with anti-CD20 had severe COVID-19, respectively, and there was no association between anti-CD20 treatment and severe COVID-19 (OR, 1.28; 95% CI, 0.76-2.16). In PMS subgroup analysis, anti-CD20 exposure interacted negatively with EDSS score ( P = .009 for interaction) and age ( P = .03 for interaction); anti-CD20 therapies were associated with risk of severe COVID-19 only in patients with less neurologic disability and younger patients with PMS. Conclusions and Relevance In this cohort study, risk of severe COVID-19 was higher in patients with PMS than in those with RRMS. Use of anti-CD20 therapies was associated with an increased risk of severe COVID-19 among patients with RRMS. In patients with PMS, there was no association between anti-CD20 therapies and risk of severe COVID-19.