Abstract:

Background: COVID-19 is a viral infectious caused by novel coronavirus called as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Recent studies have shown that the level of IL-6 in the severe infection group was higher than that in the moderate group, suggesting that IL-6 can be used as a biomarker for severity assessment. However, the correlation of IL-6 levels in critically ill patients is still unknown. Tocilizumab is a monoclonal antibody against the IL-6 receptor and commonly used for cytokine storm or macrophage activation syndrome (MAS) in COVID-19 patients. Objective: In this study, we wanted to compare the clinical outcomes of different doses of tocilizumab (400 mg and 800 mg) as treatment. Methods:In this retrospective analysis we have included 120 patients with mild Acute Respiratory Distress Syndrome (ARDS) associated with COVID-19 pneumonia who received tocilizumab 400 mg once or twice daily. The two treatment groups were compared in terms of age, gender, comorbid diseases, arterial oxygen pressure (PaO2), oxygen saturation (SaO2) on room air, admission to the intensive care, length of stay in the intensive care unit, status of intubation, mortality, C reactive protein, white blood cell count, platelets, neutrophil, lymphocyte, ferritin, D-dimer, procalcitonin levels. Results: There were no statistically significant difference between the two dosing regimens in gender, arterial oxygen pressure (PaO2), oxygen saturation (SaO2) on room air, comorbidities, need for intubation, mortality, requirement for intensive care, total length of hospital stay, length of stay in intensive care, CRP, WBC, platelets, neutrophils, lymphocytes, ferritin, D-dimer and procalcitonin levels. Conclusion : Currently the short and long term adverse effects of tocilizumab have not been clearly reported in the literature. The clinical outcomes of once or twice daily tocilizumab did not differ significantly in terms of efficacy. Therefore a single dose of 400 mg once daily tocilizumab could be a rational treatment option.