Tocilizumab, an anti-interleukin-6 receptor, administrated during the right timeframe may be beneficial against coronavirus-disease-2019 (COVID-19) pneumonia All patients admitted for severe COVID-19 pneumonia (SpO2 2-support >= 6 L/min) without invasive mechanical ventilation were included in a retrospective cohort study in a primary care hospital The treatment effect of a single-dose, 400 mg, of tocilizumab was assessed by comparing those who received tocilizumab to those who did not Selection bias was mitigated using three statistical methods Primary outcome measure was a composite of mortality and ventilation at day 28 A total of 246 patients were included (106 were treated with tocilizumab) Overall, 105 (42 7%) patients presented the primary outcome, with 71 (28 9%) deaths during the 28-day follow-up Propensity-score-matched 84 pairs of comparable patients In the matched cohort (n = 168), tocilizumab was associated with fewer primary outcomes than the control group (hazard ratio (HR) = 0 49 (95% confidence interval (95%CI) = 0 3-0 81)), (p-value = 0 005) These results were similar in the overall cohort (n = 246), with Cox multivariable analysis yielding a protective association between tocilizumab and primary outcome (adjusted HR = 0 26 (95%CI = 0 135-0 51, p = 0 0001)), confirmed by inverse probability score weighting (IPSW) analysis (p < 0 0001) Analyses on mortality only, with 28 days of follow-up, yielded similar results In this study, tocilizumab 400 mg in a single-dose was associated with improved survival without mechanical ventilation in patients with severe COVID-19