Tocilizumab for the treatment of adult patients with severe COVID‐19 pneumonia: A single‐center cohort study

Coronavirus disease 2019 (COVID‐19) can lead to a massive cytokine release. The use of the anti‐interleukin‐6 receptor monoclonal antibody tocilizumab (TCZ) has been proposed in this hyperinflammatory phase, although supporting evidence is limited. We retrospectively analyzed 88 consecutive patients with COVID‐19 pneumonia that received at least one dose of intravenous TCZ in our institution between 16 and 27 March 2020. Clinical status from day 0 (first TCZ dose) through day 14 was assessed by a 6‐point ordinal scale. The primary outcome was clinical improvement (hospital discharge and/or a decrease of ≥2 points on the 6‐point scale) by day 7. Secondary outcomes included clinical improvement by day 14 and dynamics of vital signs and laboratory values. Rates of clinical improvement by days 7 and 14 were 44.3% (39/88) and 73.9% (65/88). Previous or concomitant receipt of subcutaneous interferon‐β (adjusted odds ratio [aOR]: 0.23; 95% confidence interval [CI]: 0.06‐0.94; P = .041) and serum lactate dehydrogenase more than 450 U/L at day 0 (aOR: 0.25; 95% CI: 0.06‐0.99; P = .048) were negatively associated with clinical improvement by day 7. All‐cause mortality was 6.8% (6/88). Body temperature and respiratory and cardiac rates significantly decreased by day 1 compared to day 0. Lymphocyte count and pulse oximetry oxygen saturation/FiO2 ratio increased by days 3 and 5, whereas C‐reactive protein levels dropped by day 2. There were no TCZ‐attributable adverse events. In this observational single‐center study, TCZ appeared to be useful and safe as immunomodulatory therapy for severe COVID‐19 pneumonia. Highlights COVID‐19 can lead to a hyperinflammatory state that mirrors the cytokine release syndrome. The off‐labeluse of the anti‐interleukin‐6 receptor monoclonal antibody tocilizumab has been proposed to abrogate this deleterious inflammatory response, although the supporting evidence is scarce. In the present single‐centre study comprising 88 consecutive patients with COVID‐19 pneumonia that received at least one dose of intravenous tocilizumab between March 16 and 27, 2020, the rates of clinical improvement (defined by discharge to home and/or a decrease of = 2 points on a six‐point ordinal scale) were 44.3% (39/88) and 73.9% (65/88) by days 7 and 14, respectively. The previous or concomitant use of interferon‐β and baseline serum lactate dehydrogenase levels >450 U/L were negatively associated with clinical improvement by day 7. All‐cause mortality was 6.8%