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

Abstract

ObjectivesTo 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.MethodsThis 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.ResultsThe 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).ConclusionTocilizumab was significantly associated with better survival and greater clinical improvement in severe or critical COVID‐19 patients.