ADA, OH — Selecting appropriate treatments for multiple sclerosis is complicated by the COVID-19 pandemic, according to a new study.

With a high level of cases expected to linger, “Decisions regarding initiation or continuation of disease-modifying therapy for multiple sclerosis have to consider the potential relevance to the pandemic,” according to the report in the journal CNS Drugs.1

The study led by researchers from Ohio Northern University and including participation from the VA Multiple Sclerosis Center of Excellence at the Cleveland VAMC, pointed out that, especially now, clinicians must understand the mechanism of action and the possible idiosyncratic effects of each therapeutic agent on the immune system.

“The infectious side-effect profile as well as the route and frequency of administration of each therapeutic agent should be carefully considered when selecting a new treatment or deciding on risk mitigation strategies for existing therapy,” the authors emphasized. “More importantly, the impact of each agent on the future severe acute respiratory syndrome coronavirus type-2 (SARS-CoV-2) vaccine should be carefully considered in treatment decisions.”

The article noted that some multiple sclerosis therapies could have beneficial antiviral effects against SARS-CoV-2, while others might have beneficial immune-modulating effects against the cytokine storm and hyperinflammatory phase of the disease.

The authors suggested that conventional injectables have a favorable immune profile without an increased exposure risk and “therefore may be suitable for mild multiple sclerosis during the pandemic.” They cautioned, however, that moderate and highly active multiple sclerosis will continue to require treatment with oral or intravenous high-potency agents. In that case, they recommended risk mitigation strategies, adding that immune-modulating therapies such as the fumerates, sphinogosine-1P modulators and natalizumab “might be anecdotally preferred over cell-depleting immunosuppressants during the pandemic from the immune profile standpoint.”

As for cell-depleting agents, the study team advised that “selective (ocrelizumab) or preferential (cladribine) depletion of B cells may be relatively safer than non-selective depletion of lymphocytes and innate immune cells (alemtuzumab).”

They cautioned that patients who develop severe iatrogenic or idiosyncratic lymphopenia should be advised to maintain social distancing even in areas where lockdown has been removed or ameliorated. In addition, patients with iatrogenic hypogammaglobulinemia might require prophylactic intravenous immunoglobulin therapy in certain situations, the study noted.

The situation will continue to be complicated when the future SARS-CoV-2 vaccine becomes available, the researchers predicted, stating that patients with multiple sclerosis should be advised that certain therapies might interfere with mounting a protective immune response to the vaccine and that serological confirmation of a response could be required after vaccination.

“They should also be aware that most multiple sclerosis therapies are incompatible with live vaccines if a live SARS-CoV-2 vaccine is developed,” the authors explained. “In this article, we review and compare disease-modifying therapies in terms of their effect on the immune system, published infection rates, potential impact on SARS-CoV-2 susceptibility, and vaccine-related implications. We propose risk mitigation strategies and practical approaches to disease-modifying therapy during the COVID-19 pandemic.”


  1. Zheng C, Kar I, Chen CK, et al. Multiple Sclerosis Disease-Modifying Therapy and the COVID-19 Pandemic: Implications on the Risk of Infection and Future Vaccination [published online ahead of print, 2020 Aug 11]. CNS Drugs. 2020;1-18. doi:10.1007/s40263-020-00756-y