Tocilizumab in Critically Ill COVID-19 Patients: An Observational Study

Abstract

Tocilizumab is one of the IL-6 antagonists hypothesized to decrease the inflammatory response in the cytokine storm, postulated to be one of the mechanisms behind development of ARDS in COVID-19 patients. The objective of our study was to determine the response of tocilizumab in patients suffering from SARS-CoV-2 by analyzing the clinical parameters and inflammatory markers. A single-arm observational study was conducted from March 15, 2020, to March 15, 2021. The clinical outcomes in terms of mortality, weaning from mechanical ventilator, improvement in laboratory parameters including inflammatory cytokines and length of hospital stay were documented. Reduction in values of inflammatory markers and patients discharged home in stable condition was defined as improvement after tocilizumab administration. A total of 514 patients received tocilizumab. Critically sick patients 333 (64.8%) constituted he majority of study population. 363 (70.6%) patients were discharged home. Overall mean length of stay was found to be 11.50 ± 8.4 days. There was significant difference in length of stay of patients who required invasive mechanical ventilation as compared to those who were kept only on supplemental oxygen ( p <0.05) . Patients who were discharged showed significant improvement in all inflammatory markers and neutrophil to lymphocyte ratio as compared to those who expired ( p <0.05). 21 (4.1%) patients had a positive blood culture while 57 (11.1%) had a positive tracheal aspirate. In conclusion, tocilizumab is a reasonable therapeutic option for worsening COVID-19 pneumonia by decreasing the need for mechanical ventilation. However, its use is associated with significant adverse events including secondary bacterial and fungal infections.