A Patent Review on SARS Coronavirus Papain-Like Protease (PL^pro ) Inhibitors

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is an unprecedented global health emergency causing more than 6.6 million fatalities by 31 December 2022. So far, only three antiviral drugs have been granted emergency use authorisation or approved by the FDA. The SARS-CoV-2 papain-like protease (PL^pro ) is deemed an attractive drug target as it plays an essential role in viral polyprotein processing and pathogenesis although no inhibitors have yet been approved. This patent review discusses coronavirus PL^pro inhibitors reported in patents published between 1 January 2003 to 2 March 2023, giving an overview on the inhibitors that have generated commercial interest, especially amongst drug companies.