COVID-19 and high-efficacy multiple sclerosis therapies: Time for business as usual?

During the Coronavirus-19 (COVID-19) pandemic, many neurologists have adopted a cautious approach to treating multiple sclerosis (MS) by delaying lymphocyte-depleting therapies (Cladribine, Alemtuzumab, anti-CD20 agents), due to concerns that treatment may increase the risk and/or severity of COVID-19 infection.[1]

In this issue of Multiple Sclerosis Journal, two patients are reported who received treatment with Cladribine[2] or Rituximab[3] during the escalating COVID-19 pandemic in Europe. Both patients were hospitalized within a month of treatment with confirmed COVID-19 infection. Remarkably, despite severe lymphopenia due to recent Cladribine or undetectable B-lymphocyte counts from long-term Rituximab therapy, both patients only developed moderate COVID-19 pneumonia with good recovery. These new cases add to an increasing number of reports of favourable outcomes in MS patients receiving high-efficacy, lymphocyte-depleting therapies who have developed COVID-19 infection.[4,5]

In the vast majority of people with MS, COVID-19 produces a mild illness.[6] Preliminary data suggest that older age, comorbidities and more advanced physical disability are more strongly associated with poor outcomes in people with MS with COVID-19 than disease-modifying therapy use.[6] With falling rates of new COVID-19 infections in most countries, and reassuring reports of mild COVID-19 infection even in our most immunosuppressed patients, are we now ready for business as usual when treating MS? The answer is probably yes, and in many otherwise healthy, young adults with MS, the risks of disability worsening from delayed initiation or re-treatment with a high-efficacy treatment (or opting for a less effective treatment) will outweigh the potential risks of severe COVID-19 infection.