Inhaled Nitric Oxide for postexposure chemoprophylaxis of COVID-19
Abstract Background: Postexposure prophylaxis has been an overlooked strategy in the context of COVID-19. Inhaled Nitric Oxide offers itself as a potential tool in this context. The aim of this systematic review was to depict previous in vivo and in vitro studies demonstrating an antiviral role for NO Methodology:Embase, Medline and the Cochrane Central Register were used to search for specific keywords such as “Nitric oxide” AND “Antiviral activity” for relevant publications up to 1st of June 2021. The systematic review was performed using PRISMA protocolResults:Twenty-one studies were identified depicting an antiviral role for Nitric Oxide. Those studies involved sixteen viruses. Only four of the depicted studies were clinical trials, while three were performed on a murine model. The remainder of the studies involved in vitro experimentation of the role of NO in halting viral replication of several viruses including SARS-CoV-2Conclusion: While early reports of NO role in the treatment of COVID-19 suggested its use for the treatment of established ARDS, NO seems to have a much earlier and more efficient prophylactic role. It inhibits a protease needed for canonical viral replication of SARS-CoV-2, namely Furin, by decreasing calcium's cytosolic levels. This might add a significant tool for postexposure chemoprophylaxis in the at-risk group, especially medical personnel.