Potential therapeutic use of ebselen for COVID-19 and other respiratory viral infections

Sies, Helmut; Parnham, Michael J.

Ebselen is an organoselenium compound exhibiting hydroperoxide- and peroxynitrite-reducing activity, acting as a glutathione peroxidase and peroxiredoxin enzyme mimetic. Ebselen reacts with a multitude of protein thiols, forming a selenosulfide bond, which results in pleiotropic effects of antiviral, antibacterial and anti-inflammatory nature. The main protease (M(pro)) of the corona virus SARS-CoV-2 is a potential drug target, and a screen with over 10,000 compounds identified ebselen as a particularly promising inhibitor of M(pro) (Jin, Z. et al. (2020) Nature 582, 289–293). We discuss here the reaction of ebselen with cysteine proteases, the role of ebselen in infections with viruses and with other microorganisms. We also discuss effects of ebselen in lung inflammation. In further research on the inhibition of M(pro) in SARS-CoV-2, ebselen can serve as a promising lead compound, if the inhibitory effect is confirmed in intact cells in vivo. Independently of this action, potential beneficial effects of ebselen in COVID-19 are ascribed to a number of targets critical to pathogenesis, such as attenuation of inflammatory oxidants and cytokines.