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

Trop Med Int Health. 2021 Dec;26(12):1689-1699. doi: 10.1111/tmi.13685. Epub 2021 Oct 19.

Abstract

Objectives: To assess the effectiveness and safety of tocilizumab, a humanised anti-interleukin-6 receptor antibody, in the treatment of critical or severe coronavirus disease 2019 (COVID-19) patients.

Methods: This was a retrospective cohort study of severe or critical COVID-19 patients (≥18 years) admitted to one hospital in Kuwait. Fifty-one patients received intravenous tocilizumab, while 78 patients received the standard of care at the same hospital. Both groups were compared for clinical improvement and in-hospital mortality.

Results: The tocilizumab (TCZ) group had a significantly lower 28-day in-hospital mortality rate than the standard-of care-group (21.6% vs. 42.3% respectively; p = 0.015). Fifty-five per cent of patients in the TCZ group clinically improved vs. 11.5% in the standard-of-care group (p < 0.001). Using Cox-proportional regression analysis, TCZ treatment was associated with a reduced risk of mortality (adjusted hazard ratio 0.25; 95% CI: 0.11-0.61) and increased likelihood of clinical improvement (adjusted hazard ratio 4.94; 95% CI: 2.03-12.0), compared to the standard of care. The median C-reactive protein, D-dimer, procalcitonin, lactate dehydrogenase and ferritin levels in the tocilizumab group decreased significantly over the 14 days of follow-up. Secondary infections occurred in 19.6% of the TCZ group, and in 20.5% of the standard-of-care group, with no statistical significance (p = 0.900).

Conclusion: Tocilizumab was significantly associated with better survival and greater clinical improvement in severe or critical COVID-19 patients.

Keywords: Covid-19; Kuwait; mortality; survival; tocilizumab.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Monoclonal, Humanized / therapeutic use*
  • COVID-19 / epidemiology
  • COVID-19 Drug Treatment*
  • Cohort Studies
  • Female
  • Humans
  • Kuwait / epidemiology
  • Male
  • Middle Aged
  • Retrospective Studies
  • SARS-CoV-2*
  • Young Adult

Substances

  • Antibodies, Monoclonal, Humanized
  • tocilizumab