Choosing immunomodulating therapies for the treatment of COVID-19: recommendations based on placebo-controlled trial evidence

Immunomodulatory therapy has been extensively studied in randomized clinical trials for the treatment of patients hospitalized for COVID-19 with inconsistent findings. Guideline committees, reviewing the same clinical trial data, have generated different recommendations for immunomodulatory therapy. We hypothesize that trial design differences, specifically whether the study utilized an open-label or placebo-controlled design, accounted for the inconsistent mortality effects reported in clinical trials of immunomodulator therapies for COVID-19. We reviewed COVID-19 treatment guidelines (World Health Organization [WHO], Infectious Diseases Society of America [IDSA] and The National Institutes of Health [NIH]) and identified the meta-analyses associated with glucocorticoids, IL-6 inhibitors, JAK kinase inhibitors, and complement C5a inhibitors that were available to the guideline authors at the time recommendations were either made or updated. We identified a meta-analysis for each of the immunomodulator classes that are included in current COVID-19 treatment guidelines: glucocorticoids [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499–518] (cited 419), IL-6 antagonists [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499–518] (cited 419), JAK inhibitors [Kramer A, Prinz C, Fichtner F, Fischer AL, Thieme V, Grundeis F, et al. Janus kinase inhibitors for the treatment of COVID-19. Cochrane Database Syst Rev. 2022;6:CD015209] (cited 34), and complement C5a inhibitors [Tsai CL, Lai CC, Chen CY, Lee HS. The efficacy and safety of complement C5a inhibitors for patients with severe COVID-19: A systematic review and meta-analysis. Expert Rev Anti Infect Ther. 2023;21:77–86] (cited 1). Using the same randomized clinical trials, we evaluated the four meta-analyses accounting for trial design: placebo-controlled or open-label. Glucocorticoids (Risk Ratio [RR] 0.91 [95% CI, 0.49–1.69]), IL-6 inhibitors sarilumab (RR 1.17 [95% CI, 0.96–01.43]), and tocilizumab (RR 0.95 [95% CI, 0.76–1.19]) did not