Outcomes of tocilizumab therapy in severe or critical COVID-19 patients: A retrospective cohort, single-centre study

Area of Science:

• Immunology and Infectious Diseases
• Pharmacology and Therapeutics

Background:

• Severe and critical coronavirus disease 2019 (COVID-19) presents significant challenges in patient management.
• Interleukin-6 (IL-6) plays a key role in the cytokine storm associated with severe COVID-19.
• Tocilizumab, a humanized anti-IL-6 receptor antibody, is investigated for its therapeutic potential.

Purpose of the Study:

• To evaluate the effectiveness and safety of tocilizumab in treating critical or severe COVID-19.
• To compare clinical improvement and in-hospital mortality rates between tocilizumab and standard care groups.

Main Methods:

• Retrospective cohort study involving adult patients with severe or critical COVID-19.
• Comparison of 51 patients receiving intravenous tocilizumab versus 78 patients receiving standard of care.
• Assessment of clinical improvement, in-hospital mortality, and inflammatory marker levels.

Main Results:

• Tocilizumab group showed significantly lower 28-day in-hospital mortality (21.6% vs. 42.3%, p=0.015).
• Fifty-five percent of patients in the tocilizumab group achieved clinical improvement versus 11.5% in the standard care group (p<0.001).
• Tocilizumab treatment was associated with reduced mortality risk (aHR 0.25) and increased likelihood of clinical improvement (aHR 4.94); inflammatory markers decreased significantly.

Conclusions:

• Tocilizumab demonstrated significant efficacy in improving survival rates among severe or critical COVID-19 patients.
• The drug was associated with a substantially greater likelihood of clinical improvement compared to standard care.
• No significant difference in secondary infection rates was observed between the groups.