Protease Inhibitors as Promising Weapons against COVID-19: Focus on Repurposing of Drugs used to Treat HIV and HCV Infections

As a part of the efforts to quickly develop pharmaceutical treatments for COVID-19 through repurposing existing drugs, some researchers around the world have combined the recently released crystal structure of SARS-CoV-2 M^pro in complex with a covalently bonded inhibitor with virtual screening procedures employing molecular docking approaches. In this context, protease inhibitors (PIs) clinically available and currently used to treat infectious diseases, particularly viral ones, are relevant sources of promising drug candidates to inhibit the SARS-CoV-2 M^pro, a key viral enzyme involved in crucial events during its life cycle. In the present perspective, we summarized the published studies showing the promising use of HIV and HCV PIs as potential repurposing drugs against the SARS-CoV-2 M^pro.