Effect of Tocilizumab in Reducing the Mortality Rate in COVID-19 Patients: A Systematic Review with Meta-Analysis

Data supporting the use of Tocilizumab (TCZ) in COVID-19 are contrasting and inconclusive. This meta-analysis aimed to assess TCZ effectiveness in reducing the mortality rate in COVID-19 patients. PubMed, Scopus, Embase, Cochrane, WILEY, and ClinicalTrials.gov were searched to evaluate observational studies and RCTs. The outcome was the mortality rate. Forty observational studies and seven RCTs, involving 9640 and 5556 subjects treated with Standard Therapy (ST) + TCZ or ST alone, respectively, were included. In patients treated with ST+TCZ, a higher survival (Log odds ratio = -0.41; 95% CI: -0.68 -0.14; p < 0.001) was found. Subgroups analyses were performed to better identify the possible interference of some parameters in modifying the efficacy of TCZ therapy on COVID-19 mortality. Separating observational from RCTs, no statistically significant (p = 0.70) TCZ-related reduction of mortality regarding RCTs was found, while a significant reduction (Log odds ratio = -0.52; 95% CI: -0.82 -0.22, p < 0.001) was achieved regarding the observational studies. Stratifying for the use of Invasive Mechanic Ventilation (IMV), a higher survival was found in patients treated with TCZ in the No-IMV and IMV groups (both p < 0.001), but not in the No-IMV/IMV group. Meta-regression analyses were also performed. The meta-analysis of observational studies reveals that TCZ is associated with reducing the mortality rate in both severe and critically ill patients. Although the largest RCT, RECOVERY, is in line with this result, the meta-analysis of RCTs failed to found any difference between ST + TCZ and ST. It is crucial to personalize the therapy considering the patients' characteristics.