Efficacy of Tocilizumab in the treatment of severe COVID-19 patients with respiratory failure

Abstract

Objective: This study aimed to investigate the impact of tocilizumab, an IL6R inhibitor, on clinical features and laboratory tests of subjects admitted with severe COVID-19 and respiratory failure. \nMaterial and Methods: A total of 30 patients with positive polymerase chain reaction for COVID-19 and respiratory failure were analyzed in a retrospective manner. All patients received 8mg/kg body weight tocilizumab i.v. once in addition to the standard COVID-19 treatment protocol, including Oseltamivir phosphate 75mg twice daily, hydroxychloroquine 200 mg twice daily, and azitromycine 250 mg once daily following a 500 mg loading dose. Demographic characteristics, and clinical features including oxygen saturation, the concentration of oxygen inhalation, body temperature, mean arterial pressure and heart rate, and SpO2, end-tidal CO2, and blood tests including complete blood count, procalcitonin, C-reactive protein (CRP), Troponin-I, D-dimer, and liver and kidney function tests were recorded before and after treatment with tocilizumab. \nResults: A significant increase occurred in SaO2 on first and third days following treatment with tocilizumab (84.3 % and 90.3%, respectively, p<0.001 for both recordings compared to baseline). There was also a significant increase in end-tidal CO2. The increase in mean SaO2 after tocilizumab was followed by a decline in respiratory rate on the first and third days of treatment.\xa0 A dramatic decline was observed in body temperature from the first day of treatment with tocilizumab. Lymphocyte count increased following tocilizumab and C-reactive protein and Troponin I levels were reduced. \nConclusion: Tocilizumab appears as an effective therapeutic option for improving oxygenation, symptoms and laboratory surrogates of ongoing inflammation in subjects with severe COVID-19.