Anti-interleukin-6 therapies for Covid-19: A systematic review, critical appraisal and meta-analysis

Tocilizumab for COVID-19: A systematic review and meta-analysis of randomized controlled trials

The effective treatment modalities for severe coronavirus disease 2019 (COVID-19) are needed. As the primary cause of mortality is a hyperinflammatory state, the interleukin-6 antagonist tocilizumab has been used in multiple clinical studies. We conducted this systematic review and meta-analysis to estimate the effectiveness of tocilizumab in reduction of mortality due to COVID-19. A systematic search of the Pubmed and Embase databases was performed to extract randomized controlled trials (RCTs) regarding the use of tocilizumab therapy for COVID-19. An overall pooled mortality analysis was performed, and odds ratios were reported. Cochrane risk of bias assessment tool was used to assess the risk of bias. Heterogeneity was assessed using the I2 statistic. Nine RCTs, including 6489 patients, were selected for meta-analysis. Seven trials reported 28-day mortality, and one trial each reported 21-day and 30-day mortality. There were 846 deaths among 3358 participants in the steroid group while 943 deaths among 3131 patients randomized to the control group (random-effects odds ratio 0.87, 95% confidence interval 0.73-1.03, p=0.11). There was some heterogeneity among the trials as the I2 value was 15%, with a p-value of 0.31. There was a reduction in the need for ICU admission in the tocilizumab group. A higher risk of secondary infections was noted in the tocilizumab group (fixed-effects odds ratio 0.72, 95% confidence interval 0.55-0.95, p=0.02). This meta-analysis of RCTs demonstrated that the use of tocilizumab was not associated with a reduction in all-cause mortality in patients with COVID-19 and had higher odds of secondary infections.