Different disease modifying therapies can increase or decrease Covid-19 severity in Multiple Sclerosis

ABSTRACT

Objective: To describe the effect of disease modifying therapies (DMT) on Covid-19 severity in a large cohort of Italian patients with Covid-19 and multiple sclerosis (MS). Background: We previously presented data from a nationwide study of persons with MS with suspected or confirmed Covid-19, collected from March 2020. In June we started collecting also asymptomatic patients, when serological tests started to be routinely done. Design/Methods: This was a retrospective multi-center observational study. We defined Covid-19 severity as a 4-level variable Level 1=asymptomatic, level 2=symptomatic without signs of pneumonia, level 3=radiologically defined pneumonia or hospitalization, level 4=intensive care unit (ICU) or death. We analysed the impact of baseline variables on this outcome by a multivariable ordinal logistic model quantifying the association by Odds Ratio (OR). Results: On October 12, we enrolled 902 MS patients, 298 (33%) with confirmed and 604 (67%) with suspected Covid-19;37 (4%) were asymptomatic. The number of ICU/deaths were 8/95 (8%) among those treated with anti-CD20 therapies (mean age=41 years), 0/84 (0%) among those treated with Interferon (mean age=47 years) and 37/723 (5%) among those treated with other drugs (mean age=43 years). Among the 37 asymptomatic patients, 7/84 (8.3%) were in Interferon, 1/95 (1.1%) was on anti-CD20 and 29/723 (4%) were on other drugs. At multivariable analysis, independent risk factors for a severe Covid-19 were age (OR=1.05, p<0.001), EDSS(OR=1.13, p=0.02), Male sex(OR=1.44, p=0.057) and DMT used Treatment with anti-CD20 (Ocrelizumab or Rituximab) increased the risk (OR=1.99, p=0.035) and treatment with Interferon reduced the risk (OR=0.48, p=0.05) of severe Covid-19 as compared to treatment with DMF, used as the reference DMT. Conclusions: This analysis confirms on a larger population the increase of risk of severe Covid-19 of anti-CD20 therapies and highlights the protective role of Interferon. Data on asymptomatic patients are rapidly accumulating and will provide useful information about this.