Immunomodulatory therapies for SARS-CoV-2 infection: a systematic literature review to inform EULAR points to consider

Abstract

Objective: To summarise the available information on efficacy and safety of immunomodulatory agents in SARS-CoV-2 infection.

Methods: As part of a European League Against Rheumatism (EULAR) taskforce, a systematic literature search was conducted from January 2019 to 11 December 2020. Two reviewers independently identified eligible studies according to the Population, Intervention, Comparator and Outcome framework and extracted data on efficacy and safety of immunomodulatory agents used therapeutically in SARS-CoV-2 infection at any stage. The risk of bias was assessed with validated tools.

Results: Of the 60 372 records, 401 articles were eligible for inclusion. Studies were at variable risk of bias. Randomised controlled trials (RCTs) were available for the following drugs: hydroxychloroquine (n=12), glucocorticoids (n=6), tocilizumab (n=4), convalescent plasma (n=4), interferon beta (n=2), intravenous immunoglobulins (IVIg) (n=2) and n=1 each for anakinra, baricitinib, colchicine, leflunomide, ruxolitinib, interferon kappa and vilobelimab. Glucocorticoids were able to reduce mortality in specific subsets of patients, while conflicting data were available about tocilizumab. Hydroxychloroquine was not beneficial at any disease stage, one RCT with anakinra was negative, one RCT with baricitinib+remdesivir was positive, and individual trials on some other compounds provided interesting, although preliminary, results.

Conclusion: Although there is emerging evidence about immunomodulatory therapies for the management of COVID-19, conclusive data are scarce with some conflicting data. Since glucocorticoids seem to improve survival in some subsets of patients, RCTs comparing glucocorticoids alone versus glucocorticoids plus anticytokine/immunomodulatory treatment are warranted. This systematic literature review informed the initiative to formulate EULAR 'points to consider' on COVID-19 pathophysiology and immunomodulatory treatment from the rheumatology perspective.

Keywords: immune system diseases; inflammation; therapeutics.

Figure 1

Forest plots showing the risk ratio (RR) and 95% CI for mortality in randomised controlled trials divided by intervention. The latest follow-up available is reported in the timing column. Panel A shows RRs in overall cohorts, panel B shows overall cohorts and subgroup analysis in studies assessing glucocorticoids and panel C shows all studies on tocilizumab (including grey literature).