Outcomes in Patients with Severe COVID-19 Disease Treated with Tocilizumab - A Case- Controlled Study.

BACKGROUND: COVID-19 is an ongoing threat to society. Patients who develop the most severe forms of the disease have high mortality. The interleukin-6 inhibitor tocilizumab has the potential to improve outcomes in these patients by preventing the development of cytokine release storm. METHODS: We conducted a retrospective, case-control, single-center study in patients with severe to critical COVID-19 disease treated with tocilizumab. Disease severity was defined based on the amount of oxygen supplementation required. The primary endpoint was the overall mortality. Secondary endpoints were mortality in non-intubated patients, and mortality in intubated patients. RESULTS: A total of 193 patients were included in the study. 96 patients received tocilizumab, while 97 served as control group. The mean age was 60 years. Patients over 65 years represented 43% of the population. More patients in the tocilizumab group reported fever, cough, and shortness of breath (83%, 80%, and 96% versus 73%, 69%, and 71%, respectively). There was a non-statistically significant lower mortality in the treatment group (52% versus 62.1% P = 0.09). When excluding intubated patients, there was statistically significant lower mortality in patients treated with tocilizumab (6 vs. 27% P = 0.024). Bacteremia was more common in the control group (24% vs 13% P = 0.43), while fungemia was the similar for both (3% vs 4% P = 0.72). CONCLUSION: Our study showed a non-statistically significant lower mortality in patients with severe to critical COVID-19 disease who received tocilizumab. When intubated patients were excluded, the use of tocilizumab was associated with lower mortality.