Efficacy and Safety of Tocilizumab in the Treatment of SARS-Cov-2 Related Pneumonia

Overview

The current spread of the COrona VIrus Disease-2019 (COVID-19) epidemic in Italy, and the current lack of effective and approved drugs for its treatment, poses the problem of Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infected patients management, especially those who underwent to experience COVID-19 complications, such as CRS. This unmet need becomes more severe if the investigator consider that, the COVID-19 mortality stands around 2% in the general population, but it rises to 49% when considering intensive care unit (ICU) patients. To increase the chances of survival of these patients, the compassionate use of the available drugs is required, based on literature data, to the best of our abilities. ICU patients with cytokine release syndrome (CRS) secondary to COVID-19, show increased production of pro-inflammatory cytokines, including interleukin (IL-6), IL-2, IL-7, IL-10, tumor necrosis factor (TNF)-α and interferon (INF)γ, similar to that found in patients who develop CRS secondary to Chimeric Antigen Receptor-T (CAR-T) therapy. Although immuno-modulatory therapy is not routinely recommended in COVID-19 pneumonia, tocilizumab might have a rationale in those patients who develop CRS, blocking the complications caused by high levels of IL-6, and possibly preventing the development of a multi-organ failure. Reassuring data in this sense, come from the first studies conducted in China. In a Chinese pilot study, Xiaoling Xu and collaborators used tocilizumab (at a dosage of 400 mg iv in a single dose, with a possible second dose in case of no clinical response) in patients with COVID-19 in the presence of one of the following criteria: i) respiratory rate ≥ 30 acts/min; ii) SpO2 ≤ 93% in ambient air; iii) PaO2/FiO2 ≤ 300 mmHg. In the 21 patients treated with tocilizumab a significant reduction in IL-6 levels and fever, with improvement in lung function, was demonstrated. Besides, 90% of treated patients showed an improvement in the radiological picture, in terms of a decrease in the frosted glass areas, and a return to normal lymphocytes count in the peripheral blood. This is a prospective observational clinical study and it is aimed at verifying tocilizumab efficacy and safety in patients with COVID-19 complicated by acute distress respiratory syndrome (ARDS) and CRS.