Does tocilizumab have a magical therapeutic effect on COVID-19 patients without obvious adverse reactions?

Coronavirus disease 2019 (COVID-19) may cause a cytokine storm, which may lead to respiratory failure or even death, and the mortality rate for critically ill cases reached 60.5% (1, 2). In a retrospective observational study conducted by Xu et al. (3), all 21 patients, including 17 seriously ill and 4 critically ill cases (4), had been discharged after an average of 15.1 d, and no patient died after taking tocilizumab (TCZ). This indicates that TCZ has almost a magical therapeutic effect on COVID-19 patients. However, our findings are not optimistic. In Taikang Tongji Hospital, all 12 patients with elevated interleukin-6 (IL-6) levels, … [↵][1]1To whom correspondence may be addressed. Email: xiangdongzhou{at}126.com or qingmao{at}tmmu.edu.cn. [1]: #xref-corresp-1-1