Abstract
The in-hospital mortality in patients with COVID-19 could be correlated with severe acute respiratory syndrome coronavirus-2 induced hyper-inflammation, which is attributed to an unconstrained inflammatory cytokine storm. The pro-inflammatory cytokine, specifically, interleukin-6 plays a prominent role in the cytokine storm and may result in alveolar-capillary blood-gas exchange dysfunction. Therefore, the method to block the signal transduction pathway of interleukin-6 could be a potential treatment for severe COVID-19 patients. In this case series of three patients with severe COVID-19, we focus on the rationale for utilization of tocilizumab, an anti-interleukin-6 receptor antibody, which could block the signal transduction pathway of interleukin-6. The observations from this study allowed us to hypothesize that the infusions of tocilizumab may not reduce the elevated level of interleukin-6, and hence may not be a significant therapeutic for reducing in-hospital mortality associated with COVID-19. Additionally, it could also be speculated that interleukin-6 may not be a potentially actionable target cytokine to treat COVID-19-associated cytokine storms. KEYWORDS: COVID-19; cytokines; interleukin-6.