Abstract
OBJECTIVES: Severe COVID-19 is associated with an imbalanced immune response. We hypothesized that patients with enhanced inflammation, as demonstrated by increased levels of certain inflammatory biomarkers, would benefit from interleukin-6 blockage. METHODS: Patients hospitalized with COVID-19, hypoxemia, and at least two of four markedly elevated markers of inflammation (interleukin-6, C-reactive protein, ferritin, and/or D-dimer) were randomized for tocilizumab (TCZ) plus standard of care (SoC) or SoC alone. The primary endpoint was clinical status at day 28 assessed using a seven-category ordinal scale, and the secondary endpoints included intensive care unit admission, respiratory support, and duration of hospital admission. RESULTS: Clinical status at day 28 was significantly better in patients who received TCZ in addition to SoC compared with those who received SoC alone (p = 0.037). By then, 93% of patients who received TCZ (n = 53 of 57) and 86% of control patients (n = 25 of 29) had been discharged from the hospital. In addition, 47% of TCZ patients (n = 27 of 57) and 24% of control patients (n = 7 of 29) had resumed normal daily activities. The median length of hospitalization was 9 days (interquartile range, 7-12) in the TCZ group and 12 days (interquartile range, 9-15) in the control group (p = 0.014). DISCUSSION: In patients hospitalized with COVID-19, hypoxemia, and elevated inflammation markers, administration of TCZ in addition to SoC was associated with significantly better clinical recovery by day 28 and a shorter hospitalization compared with SoC alone.