Abstract
Although many potent drugs have been used for cytokine storm, mortality is high for patients with coronavirus disease-2019 (COVID-19), which is followed up in the intensive care unit. Interferons (IFNs) are the major cytokines of the antiviral defense system released from many cell types. However, IFN-γ plays a key role in both primary and secondary cytokine storms. If the cytokine storm is not treated urgently, it will be fatal; therefore, it should be treated immediately. Anakinra, an interleukin-1 (IL-1) antagonist, tocilizumab, an IL-6 antagonist, and Janus kinase (JAK) inhibitors are successfully used in cytokine storm caused by COVID-19. However, sometimes, despite these treatments, the patient's clinical course does not improve. Emapalumab (Eb) is the human immunoglobulin G1 monoclonal antibody and is a potent and noncompetitive antagonist of IFN-γ. Eb can be life saving for cytokine storm caused by COVID-19, which is resistant to anakinra, tocilizumab, and JAK inhibitors.