Tocilizumab improves 28-day survival in hospitalized patients with severe COVID-19: an open label, prospective study

BACKGROUND: Data on the safety and efficacy profile of tocilizumab in patients with severe COVID-19 needs to be enriched. METHODS: In this open label, prospective study, we evaluated clinical outcomes in consecutive patients with COVID-19 and PaO(2)/FiO(2) < 200 receiving tocilizumab plus usual care versus usual care alone. Tocilizumab was administered at the time point that PaO(2)/FiO(2) < 200 was observed. The primary outcome was 28-day mortality. Secondary outcomes included time to discharge, change in PaO(2)/FiO2 at day 5 and change in WHO progression scale at day 10. FINDINGS: Overall, 114 patients were included in the analysis (tocilizumab plus usual care: 56, usual care: 58). Allocation to usual care was associated with significant increase in 28-day mortality compared to tocilizumab plus usual care [Cox proportional-hazards model: HR: 3.34, (95% CI: 1.21–9.30), (p = 0.02)]. There was not a statistically significant difference with regards to hospital discharge over the 28 day period for patients receiving tocilizumab compared to usual care [11.0 days (95% CI: 9.0 to 16.0) vs 14.0 days (95% CI: 10.0–24.0), HR: 1.32 (95% CI: 0.84–2.08), p = 0.21]. ΔPaO(2)/FiO(2) at day 5 was significantly higher in the tocilizumab group compared to the usual care group [42.0 (95% CI: 23.0–84.7) vs 15.8 (95% CI: − 19.4–50.3), p = 0.03]. ΔWHO scale at day 10 was significantly lower in the tocilizumab group compared to the usual care group (-0.5 ± 2.1 vs 0.6 ± 2.6, p = 0.005). CONCLUSION: Administration of tocilizumab, at the time point that PaO(2)/FiO(2) < 200 was observed, improved survival and other clinical outcomes in hospitalized patients with severe COVID-19 irrespective of systemic inflammatory markers levels. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12931-021-01914-6.