Tocilizumab therapy in COVID-19 patients

Abstract

A severe pneumonia-associated respiratory syndrome caused by the new coronavirus 2 (SARS‑CoV‑2) was identified in December 2019 as Coronavirus Disease 2019 (COVID-19). It has spread rapidly and has become a worldwide health challenge. Some patients experienced severe complications, including acute respiratory distress syndrome (ARDS), and have even progressed to an intensive care unit (ICU) admission and death. Research has reported that pathogenic T cells and inflammatory monocytes prompt an inflammatory storm with large amounts of interleukin 6. Consequently, IL-6 receptor inhibitors have been repurposed to treat COVID-19, but their exact role in treatment remains unclear. Tocilizumab (TCZ), a monoclonal antibody against IL-6, emerged as an alternative treatment in COVID-19 patients with ARDS syndrome. Therefore, the authors hypothesise that tocilizumab might be effective in decreasing the inflammatory storm and reducing mortality in COVID-19 severe cases. This observational retrospective study explored the use of a single dose of tocilizumab 400 mg intravenous infusion for an hour in COVID-19 patients. The results showed that tocilizumab could not improve the parameters related to mortality rates, such as IL-6 levels, leukocytes, C-reactive protein (CRP), Neutrophil-to-lymphocyte ratio (NLR), and ferritin. IL-6 levels increased after tocilizumab administration.