Overview on the use of IL-6 agents in the treatment of patients with cytokine release syndrome (CRS) and pneumonitis related to COVID-19 disease

Expert Opin Investig Drugs. 2020 Dec;29(12):1407-1412. doi: 10.1080/13543784.2020.1840549. Epub 2020 Dec 1.


Introduction: A novel coronavirus pneumonia (COVID-19) has caused significant life loss and healthcare burden globally. COVID-19 is known to cause a cytokine release syndrome (CRS) like response, and interleukin-6 (IL-6) is one of the cytokines involved. Clinicians are using IL-6 inhibitors to CRS, and researchers are investigating the use of IL-6 inhibitors, namely tocilizumab, sarilumab, siltuximab, in COVID-19 management.

Areas covered: In this article, we will discuss the pharmacology of these three inhibitors and summarize available clinical data via literature search on PubMed with keywords of tocilizumab, sarilumab, siltuximab, and COVID-19. While awaiting more data from randomized clinical trials on these drugs, observational studies and clinical reports have demonstrated IL-6 inhibitors showed some benefits in improving clinical outcome and a well-tolerated safety profile.

Expert opinion: There is a role for suppressing the immune response with IL-6 inhibitors that will continue to require investigation. These agents are available and have demonstrated a mild safety profile. There may be advantages to a targeted approach to suppressing the hyperinflammatory state of the disease. Timing, the long-term effects, and what cocktail of medications demonstrates the strongest outcomes are all important considerations as IL-6 inhibitors continue to be evaluated in this global pandemic.

Keywords: COVID-19; cytokine release syndrome; cytokine storm; interleukin-6 inhibitors; sarilumab; siltuximab. Pneumonitis; tocilizumab.

Publication types

  • Review

MeSH terms

  • Antibodies, Monoclonal / administration & dosage*
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • COVID-19 / epidemiology
  • COVID-19 / immunology
  • COVID-19 Drug Treatment*
  • Clinical Trials as Topic / methods
  • Cytokine Release Syndrome / drug therapy*
  • Cytokine Release Syndrome / epidemiology
  • Cytokine Release Syndrome / immunology
  • Humans
  • Interleukin-6 / antagonists & inhibitors*
  • Interleukin-6 / immunology
  • Pneumonia / drug therapy*
  • Pneumonia / epidemiology
  • Pneumonia / immunology


  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • IL6 protein, human
  • Interleukin-6
  • tocilizumab
  • sarilumab
  • siltuximab