Tocilizumab for the treatment of COVID-19

IntroductionSince the beginning of the COVID-19 pandemic, the repurposing of medicines has been pursued to find interventions effective in preventing fatal outcome of the disease. One of these drugs was tocilizumab, an interleukin-6 inhibiting monoclonal antibody, previously used to treat several immune-related disorders.Areas coveredIn this article, we present the results of the initial observational studies and subsequent randomized clinical trials on the efficacy and safety of tocilizumab in the treatment of COVID-19. Despite conflicting results, possibly due to the heterogeneity of the studied populations, large studies have ultimately proven that preventing IL-6 from attaching to its receptors can effectively reverse the fatal course of the disease. We also discuss the meta-analyses, which mostly supported the validity of tocilizumab therapy. We show how tocilizumab found its place in the most important recommendations on COVID-19 treatment and obtained authorization from the major regulatory authorities.Expert opinionThe criteria for optimizing tocilizumab therapy in COVID-19 still need to be established. They are also important considering the existing risks of future zoonotic spillovers and epidemics that may trigger hyperinflammation that could be efficiently blocked. The experience gained with tocilizumab shall be perceived as preparedness for future challenges.