Safety of Alemtuzumab for MS During the COVID-19 Pandemic

Coronavirus around blood cells
Patients with severe MS treated with alemtuzumab displayed milder and shorter symptoms of COVID-19.

In patients with severe multiple sclerosis (MS), treatment with alemtuzumab was found to be safe during the coronavirus disease 2019 (COVID-19) pandemic, according to a case-series published in Multiple Sclerosis and Related Disorders.

While early during the pandemic there were concerns that patients receiving immunosuppressive drugs would be at increased risk for COVID-19 and adverse outcomes, additional preliminary studies suggested that treatment associated with lymphocyte depletion may result in milder disease.

Alemtuzumab, a humanized immunoglobulin (Ig) G1 antibody targeting the glycophosphatidylinositol-anchored CD52 protein with B- and T-cell depletion, is reserved for patients with severe MS. As limited data are available on the safety of alemtuzumab use during the COVID-19 pandemic, the goal of the current case-series was to explore the frequency and severity of the viral infection in patients treated with this drug.

The single-center, observational case-series included 10 alemtuzumab-treated patients (mean age 43.7 years; 80% women) with relapsing-remitting MS treated at a tertiary hospital in Madrid, Spain. The last dose of alemtuzumab was given between March 2018 and February 2020, indicating that none of the patients received alemtuzumab during the pandemic.  Contacted by phone, the patients completed a 20 min semi-structured interview to assess for symptoms suggestive of COVID-19.

Of the 10 patients enrolled in the study, 2 patients (20%) developed symptoms that were deemed highly suggestive of COVID-19. In both cases, there was no indication for hospitalization.

There were no significant differences between patients with and those without symptoms of COVID-19 with regards to age, sex, expanded disability status scale (EDSS), last lymphocyte count, and time since the last administered dose of alemtuzumab. However, the duration of MS was longer in patients with COVID-19 symptoms (29.50 ± 9.19 years vs 17.30 ± 8.59 years, respectively; P = .034).

Interestingly, the 2 alemtuzumab-treated patients with COVID-19 symptoms displayed milder and shorter forms of COVID-19, compared to other relatives also affected by the virus. Of note, neither patients were assessed by reverse transcription-polymerase chain reaction (RT-PCR) for COVID-19, although one of them had a positive serological study one month later.

The researchers acknowledged several study limitations, including the limited sample size, inclusion of patients who did not receive alemtuzumab during the pandemic, and absence of RT-PCR testing.

“[O]ur study suggests that alemtuzumab seems to be safe in the context of the COVID-19 pandemic. Furthermore, we speculate whether alemtuzumab may even be a therapeutic option for the COVID-19 infection itself, given the mechanism of action generating a reconstituted immune system more resistant to the virus and reducing the risk of the cytokine storm,” wrote the researchers.


Matías-Guiu J, Montero-Escribano P, Pytel V, Porta-Etessam J, Matías-Guiu J. Potential COVID-19 infection in patients with severe multiple sclerosis treated with alemtuzumab. (published online June 9, 2020). Mult Scler Relat Disord. doi:10.1016/j.msard.2020.102297