ABSTRACT
Background: Understanding outcomes of Coronavirus Disease 2019 (COVID-19) and the impact of COVID-19 vaccination deserve significant consideration for people with multiple sclerosis (MS) treated with ocrelizumab (OCR). Aim(s): To report the number, characteristics and outcomes of COVID-19 cases in all OCR-treated patients and in those with COVID-19 vaccination (i.e. breakthrough cases) in two realworld cohort studies. Method(s): We analysed data from OCR-treated patients enrolled in ongoing, prospective, noninterventional studies conducted in Germany (CONFIDENCE, EUPAS22951) and in 25 other countries (MuSicalE, NCT03593590). COVID-19 seriousness was assessed per ICH guidelines. Outcomes were captured as recovered, recovered with sequelae, recovering, not recovered or fatal. Vaccine breakthroughs were cases with COVID-19 onset >=14 days after completion of the primary immunisation schedule recommended for each COVID-19 vaccine platform. 'Unvaccinated' included patients without COVID-19 vaccination recorded (including the prevaccination era) or with incomplete immunisation scheme. Result(s): Analyses included 1,702 OCR-treated patients from MuSicalE (73.1% relapsing-remitting MS, 21.2% primary progressive MS [PPMS], 5.6% relapsing secondary progressive MS) and 2,784 from CONFIDENCE (81.7% relapsing MS, 18.3% PPMS). As of March 2022 (preliminary data), completion of primary immunisation schedule was recorded for 542 (31.8%) and 710 (25.5%) patients in each study, mainly with mRNA vaccines (72.3% and 93.8%). COVID-19 infection was reported in 189 and 122 patients in MuSicalE and CONFIDENCE (11.1% and 4.4% among all patients), mostly reported as nonserious (85.2% and 83.6%), including 71 and 31 vaccine breakthroughs (13.1% and 4.4% among fully vaccinated patients). The following rates were reported in vaccinated and unvaccinated patients in MuSicalE and CONFIDENCE, respectively: (a) hospitalisations, 8.5% (6/71) vs 16.0% (19/118) and 9.7% (3/31) vs 14.3% (13/91);(b) serious cases, 8.5% (6/71) vs 17.8% (21/118) and 9.7% (3/31) vs 18.7% (17/91);(c) fatalities, 1.4% (1/71) vs 2.5% (3/118) and 0 deaths vs 2.2% (2/91). In both studies, the majority of patients had fully recovered (79.9% and 74.6%) or were recovering (11.1% and 7.4%) at last follow-up. Updated vaccination rates will be presented. Conclusion(s): Most COVID-19 cases were nonserious in these OCR-treated patient cohorts. Initial data suggest more favourable clinical outcomes associated with COVID-19 vaccination.