Broad-spectrum inhibition of coronavirus main and papain-like proteases by HCV drugs

Abstract Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has led to over 200,000 deaths thus far. We screened a library of approved antiviral drugs against the two SARS-CoV-2 proteases, 3C-like/main protease (3CLpro/Mpro) and papain-like protease (PLpro), which are essential for viral replication and attractive drug targets. Three HCV protease inhibitors were tested and found to inhibit 3CLpro and PLpro enzymes from Alpha-, Beta- and Gamma-coronaviruses. Anti-HIV drugs had no activity. Boceprevir and telaprevir inhibited 3CLpro, with boceprevir inhibiting eight of nine coronavirus 3CLpro enzymes tested including from SARS-CoV-2, MERS and SARS-CoV. Asunaprevir inhibited PLpro from SARS-CoV-2 and four other coronaviruses. The 1.4 Å X-ray structure of boceprevir bound to 3CLpro was determined to explain its broad-spectrum activity and guide structure-based design of inhibitors of multiple coronaviruses.Authors Brandon J. Anson, Mackenzie E. Chapman, and Emma K. Lendy contributed equally to this work.