Efficacy of interleukin-6 inhibitors as a tool for preventive anti-inflammatory therapy for COVID-19

The novel coronavirus infection (COVID-19) is characterized by damage, along with the lungs, to many other vital organs and systems. The prevalence and severity of the resulting lesions are determined by the ability of the SARS-CoV-2 virus to cause excessive activation of the immune response, accompanied by changes in both cellular and humoral components. Among humoral disorders, the most significant is the hypersecretion of cytokines, including interleukins (IL), in particular IL-6 and IL1β. Elevated levels of IL-6 are one of the main predictors of severe COVID-19 and death. So, blocking the effects of this cytokine is of fundamental importance for improving the clinical outcomes of patients. Monoclonal antibodies against human interleukin-6 receptor or against IL-6 have been widely studied in patients with extremely severe COVID-19, and to a lesser extent in mild and moderate severity. Regardless of the severity, maximum effectiveness is achieved when these drugs are administered as early as possible, which made it possible to create such a tool as preventive anti-inflammatory therapy. Preventive prescription of IL-6 inhibitors may be useful not only for hospitalized inpatients, but also for outpatients. This review is aimed to assess the effectiveness of early use of IL-6 inhibitors both in hospitalized and ambulatory patients with varying degrees of severity of COVID-19.