Should Intravenous Immunoglobulin G (IVIg) be used in the treatment of COVID-19?

KEY FINDINGS There is conflicting evidence on the efficacy of intravenous immunoglobin G in the treatment of COVID-19 patients with severe disease. Intravenous immunoglobulin G (IVIg) is a mixture of polyclonal immunoglobulin G (IgG3, IgG4) antibodies as well as variable amounts of proteins; IgA, IgE and IgM antibodies isolated and pooled from healthy donors. IgG is involved in viral neutralization, modulates anti-inflammatory cytokines and cytokine antagonists. Immediate adverse effects of IVIg include flu-like syndrome, dermatologic side effects, arrhythmia, hypotension, and transfusion-related acute lung injury (TRALI). Delayed adverse effects can involve any organ which could be severe or even lethal There was a retrospective study (Yun Xie 2020) and several case reports that described recovery of COVID positive patients with severe disease. However, a retrospective study showed that immunoglobulin G with steroids and antivirals did not improve COVID patients with acute respiratory distress syndrome (Liu Y 2020). Similarly, another study showed no significant difference in the 28- and 60-day mortality between the IVIg and non-IVIg groups but subgroup analyses reported that in those with critical COVID illness, 28 day mortality is decreased with IVIg (Shao Z). There are eight registered clinical trials on the use of intravenous immunoglobulin G in COVID-19 patients.