Clinical characteristics and outcomes of critically ill mechanically ventilated COVID-19 patients receiving interleukin-6 receptor antagonists and corticosteroid therapy: a preliminary report from a multinational registry

Background: Interleukin-6 receptor antagonists (IL-6RAs) and steroids are emerging immunomodulatory therapies for severe and critical coronavirus disease (COVID-19). In this preliminary report, we aim to describe the epidemiology, clinical characteristics, and outcomes of adult critically ill COVID-19 patients, requiring invasive mechanical ventilation (iMV), and receiving IL-6RA and steroids therapy over the last 11 months. Materials and methods: International, multicenter, cohort study derived from Viral Infection and Respiratory Illness University Study registry and conducted through Discovery Network, Society of Critical Care Medicine. Data were collected between March 01, 2020, and January 10, 2021. Results: Of 860 patients who met eligibility criteria, 589 received steroids, 170 IL-6RAs, and 101 combinations. Patients who received IL-6RAs were younger (median age of 57.5 years vs. 61.1 and 61.8 years in the steroids and combination groups, respectively). The median C-reactive protein level was > 75 mg/L, indicating a hyperinflammatory phenotype. The median daily steroid dose was 7.5 mg dexamethasone or equivalent (interquartile range: 6–14 mg); 80.8% and 19.2% received low-dose and high-dose steroids, respectively. Of the patients who received IL-6RAs, the majority received one dose of tocilizumab and sarilumab (dose range of 600–800 mg for tocilizumab and 200–400 mg for sarilumab). Regarding the timing of administration, we observed that steroid and IL-6RA administration on day 0 of ICU admission was only 55.6% and 39.5%, respectively. By day 28, when compared with steroid use alone, IL-6RA use was associated with an adjusted incidence rate ratio (aIRR) of 1.12 (95% confidence interval [CI] 0.88, 1.4) for ventilator-free days, while combination therapy was associated with an aIRR of 0.83 (95% CI 0.6, 1.14). IL-6RA use was associated with an adjusted odds ratio (aOR) of 0.68 (95% CI 0.44, 1.07) for the 28-day mortality rate, while combination therapy was associated with an aOR of 1.07 (95% CI 0.67, 1.70). Liver dysfunction was higher in IL-6RA group (p = 0.04), while the bacteremia rate did not differ among groups. Conclusions: Discordance was observed between the registry utilization patterns (i.e., timing of steroids and IL-6RA administration) and new evidence from the recent randomized controlled trials and guideline recommendations. These data will help us to identify areas of improvement in prescribing patterns and enhance our understanding of IL-6RA safety with different steroid regimens. Further studies are needed to evaluate the drivers of hospital-level variation and their impact on clinical outcomes. Trial registration ClinicalTrials.gov: NCT04486521. Registered on July 2020.