Is There any Additional Benefit of Multiple Doses of Tocilizumab in COVID-19 Patients?

Many patients with coronavirus disease 2019 (COVID-19) have a hyperactive immune response (cytokine storm) which has been incriminated in multiorgan dysfunction (MOD). Interleukin-6 (IL-6) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are the key cytokines involved in mediating systemic inflammation and triggering endothelial dysfunction. To limit these effects, IL-6 receptor inhibitors (IL6ri) have been used in COVID-19 patients. The best approach regarding the total number of doses in COVID-19 patients is still unclear. In this single-center retrospective study, we investigated if multiple doses of tocilizumab (TCZ) prevented deterioration of COVID-19 patients. Patients were divided into two cohorts based on the number of TCZ doses; cohort 1 (received one dose) and cohort 2 (received ≥ two doses). In both cohorts, all-cause-mortality was the primary outcome. Of 270 hospitalized patients with COVID-19, 81 patients received TCZ. Fifty patients received one dose of TCZ and 31 received ≥ two doses. All-cause-mortality in cohort 2 remained higher (41.9%) suggesting that there was no additional benefit of multiple doses of TCZ to prevent the primary outcome. In addition, multiple doses of TCZ did not change any other secondary outcome [(ICU admission, acute kidney injury (AKI), acute respiratory distress syndrome (ARDS), acute cardiac injury (ACI), thrombotic events, septic shock, and total hospital stay].