ABSTRACT
BACKGROUND: Tocilizumab, an inhibitor of the interleukin-6 receptor, may decrease the inflammatory response and control the symptoms of severe coronavirus disease 2019 (COVID-19), but the evidence is scarce. METHODS: This retrospective study included patients with severe COVID-19 requiring oxygen therapy who received tocilizumab in seven centers across Poland. We assessed on-treatment changes in clinical status and inflammatory markers. RESULTS: Twenty-eight patients were included (19 male), with a mean age of 61.7 ± 12.4 years. The mean time from symptom onset to the first tocilizumab dose was 10.5 ± 5.7 days. Clinical status improved within 24 hours in 11 (39%) patients, within one week in 23 (82%) patients, and within two weeks in 25 (89%); one (4%) patient showed no change and two (7%) patients died. Sixteen patients (57%) no longer needed oxygen therapy within a week (p < 0.001). The serum concentrations of C-reactive protein, procalcitonin, and fibrinogen decreased significantly (p ≤ 0.001). Lung changes improved in 21 (84%) patients within two weeks of treatment; 19 had minimal or no changes upon final examination. CONCLUSIONS: Tocilizumab can control the symptoms of severe COVID-19 by reducing the inflammatory response and rapidly improves the clinical status in most patients.