Figure 1.

ICB therapy in patients with cancer has the potential to have beneficial or detrimental effects on infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the course of coronavirus disease 2019 (COVID-19). Blocking immune-checkpoint proteins like programmed death 1 (PD1) or cytotoxic T lymphocyte antigen 4 (CTLA4) may improve antiviral responses against SARS-CoV-2, decreasing the rate of infection or mounting a stronger immune response to the virus leading to lack of viral replication and less serve COVID-19 outcomes. Conversely, blocking immune checkpoints may result in enhanced inflammatory responses to the host induced by increased interferon pathway signaling, resulting in severe complications such as acute respiratory distress syndrome (ARDS).