Multiple Sclerosis Does Not Increase Risk of Contracting COVID-19, But Some Treatments, EDSS, and Progressive Status May Increase COVID-19 Severity

In an encore session of MS Virtual 2020, the joint American and European Committees on Treatment and Research in Multiple Sclerosis (ACTRIMS/ECTRIMS) online meeting, new data regarding SARS-COV2 infection rates in people with MS were reported. Effects of disease-modifying treatments for multiple sclerosis (MS) on severity of COVID-19 were also reported. Together the data suggest that 

• people with MS are not at higher risk of contracting COVID-19 than the general population, 
• COVID-severity may be higher in those who are not taking a DMT, 
• the antiCD20 class of DMTs may carry higher risk for severity of COVID-19 than other DMTs, and
• higher Expanded Disability Status Scale (EDSS) scores, progressive MS, and age are associated with increased COVID-19 severity.

Using data from individuals in the United Kingdom MS Register (UKMSR) who agreed to participate in a COVID-19 study, the incidence of COVID-19 in people with MS (mean age 52.4, 23.9% men, and 95.7% white) was estimated as 10% (522/5237) between March and June 2020. Weekly incidence peaked at 13.2% in the 2nd week of "lockdown" conditions in the UK in March 2020 and remained high until week 10, when it dropped to 3.5%. These rates are comparable to what was seen in the overall UK population. 

In the UKMSR study, individuals with higher EDSS scores were more likely to self-isolate (odds ratio [OR], 1.389; 95% CI, 1.333-1.447), as were those taking DMTs (OR, 1.245; 95% CI, 1.059-1.497). Individuals with progressive MS also tended to self-isolate more (OR, 1.245; 95% CI, 1.013-1.531). Among this cohort, age (OR, 0.969; 95% CI, 0.957-0.982), having progressive MS (OR, 0.595; 95% CI, 0.422-0.838), and being white (OR, 0.495; 95% CI, 0.347-0.705) were associated with a lower likelihood of having COVID-19. Gender, EDSS, and DMT use did not alter the likelihood of contracting COVID-19.

In the French COVISEP study (NCT04355611) of 405 individuals with MS who contracted COVID-19 (mean age 44.7, 27.6% men, mean MS duration 13.4 years), those not being treated with DMT (n=81) had higher rates of hospitalization and need for ventilatory support (39.2%) than for those who were using DMTs (14.4%, P<.001). Taking interferons or glatiramir acetate was associated with reduced severity of disease (OR, 0.2; 95% CI, 0.05-0.8). Increased age (10-year increments) and EDSS scores of 6 or more were independently associated with higher risks of hospitalization (OR, 1.8; 95% CI, 1.4-2.4) and more severe disease (OR, 4.5; 95% CI, 2.0-10.0). Among this cohort, 19.3% were hospitalized and 3% died from COVID-19. The median EDSS score for this cohort was 2.0 (range: 0-9.5) and 80.5% were being actively treated with a DMT.

In a search of the Roche global safety database carried out by the company's pharmacovigilance group, 201 cases of people who were taking the antiCD20 drug ocrelizumab (Ocrevus; Roche Genentech, South San Francisco, CA) and presumed to have COVID-19 were designated as serious if so identified by the reporter or, when certain regulatory conditions were met, by the company. Of these cases, 39% were considered serious, mostly because of hospitalization, and fatality was reported in 5.5%. 

In a global data sharing initiative across 21 countries, data from 1,540 individuals with MS who contracted SARS-COV2 showed treatment with ocrelizumab or rituximab, both antiCD20 agents, increased likelihood of hospitalization with adjusted prevalence ratios (aPRs) of 1.19 and 1.58, respectively. People using ocrelizumab or rituximab also had higher rates of admission to intensive care units (aPRs 3.53, 4.12, respectively), and need for artificial ventilation (aPR 3.17, 7.27, respectively) compared with those taking dimethyl fumarate. Using pooled data for those taking any antiCD20 agent, there was higher likelihood of hospitalization (aPR 1.49), admission to critical care (aPR 2.55), and artificial ventilation (aPR 3.05) than for those taking any other class of DMT or for those taking natalizumab (hospitalization aPR=1.99; ICU aPR=2.39; ventilation aPR=2.84). These correlations were independent of confirmed vs suspected COVID-19 and contributing data sources. No associations were observed between DMTs and death. This study also showed that age, progressive MS, and higher EDSS were associated with higher frequencies of severe outcomes.