IL6 and COVID-19: On the other hand, an RCT, become public soon after the end-day of our meta-analysis, demonstrated that CP was able to significantly decrease the levels of interleukin-6, tumor necrosis factor-α, and interferon (IFN)-γ, calling for more studies on the immunomodulatory effect of this treatment on COVID-19-related cytokine storm (Pouladzadeh et al., 2021).