Treat 2019 novel coronavirus (COVID-19) with IL-6 inhibitor: Are we already that far?

The world is in the midst of the coronavirus disease 2019 (COVID-19) pandemic. Interleukin 6 (IL-6) inhibitor (tocilizumab) had been suggested for the treatment of acute respiratory distress syndrome (ARDS) patients based on the concept of "cytokine storm" in COVID-19. However, we still lack reliable studies to verify "cytokine storm" in COVID-19 pneumonia. Furthermore, IL-6 inhibitor has potential hazards of inducing infectious diseases. The efficacy of IL-6 monoclonal antibody-directed therapy remains to be fully evaluated.