 Arbutus Biopharma Corporation NASDAQ: ABUS has identified several molecules that inhibit the SARS-CoV-2 nsp5 main protease Mpro, a validated target for treating COVID-19 and potential future coronavirus outbreaks. In April 2021, Arbutus, X-Chem Inc, and Proteros biostructures GmbH entered a discovery research and license agreement of novel inhibitors targeting the SARS-CoV-2 nsp5 main protease. 