CTSS and COVID-19: Furthermore, an elegant review by Pišlar and coworkers [74] reports an updated list of cathepsin inhibitors tested for Cov inhibition, including SARS-CoV-2, while a review by Liu and co-workers [145] nicely describes the antiviral properties, pharmacology, and toxicity of seven cathepsin L selective inhibitors that may represent an effective therapeutic option for COVID-19.