Disease modifying therapies and Covid-19 severity in Multiple Sclerosis

Objective: To assess the impact of immunosuppressive and immunomodulatory therapies on the severity of Coronavirus disease 2019 (Covid-19) in people with MS (PwMS).

Methods: We retrospectively collected data of PwMS with suspected or confirmed Covid-19. All the patients had complete follow up to death or recovery. Severe Covid-19 was defined by a 3-level variable: mild disease not requiring hospitalization vs pneumonia or hospitalization vs Intensive Care Unit (ICU) admission or death. We evaluated baseline characteristics and MS therapies associated to a severe Covid-19 by multivariable and Propensity-Score (PS)-weighted ordinal logistic models. Sensitivity analyses were run to confirm the results.

Results: Of 844 PwMS with suspected (n = 565) or confirmed (n = 279) Covid-19, 13 (1.54%) died: 11 of them were in a progressive MS phase, and 8 were without any therapy. Thirty-eight (4.5%) were admitted to an ICU; 99 (11.7%) had a radiologically documented pneumonia; 96 (11.4%) were hospitalized. After adjusting for region, age, sex, progressive MS course, EDSS, disease duration, BMI, comorbidities and recent methylprednisolone use, the therapy with an anti-CD20 agent (Ocrelizumab or Rituximab) was significantly associated (OR = 2.37,95%CI = 1.18-4.74,p = 0.015) with an increased risk of severe Covid-19. Recent use (<1 month) of methylprednisolone was also associated with a worse outcome (OR = 5.24,95%CI = 2.20-12.53, p = 0.001). Results were confirmed by the PS-weighted and by all the sensitivity analyses.

Interpretation: This study showed an acceptable level of safety of therapies with a broad array of mechanisms of action. However, some specific elements of risk emerged. These will need to be considered while the Covid-19 pandemic is persisting. This article is protected by copyright. All rights reserved.