Immune checkpoint inhibition in COVID-19: risks and benefits.

ICI can interrupt the T cell exhaustion and depletion by interrupting the inhibitory signaling of checkpoint molecules in T cells, and augments the immune system response in COVID-19 patients with lymphopenia. However, ICI may also increase the risk of cytokine release syndrome. ICI can be considered not only as a cancer immunotherapy but also as immunotherapy in COVID-19. More studies are needed to assess the safety of ICI in COVID-19 patients with or without cancer.