Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
Efrat Ozer Partuk
Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
Jeanne Chiaravalli
Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Chemogenomic and Biological Screening Core Facility, C2RT, Paris, France
Noga Kozer
The Wohl Drug Discovery Institute of the Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 7610001, Israel
Khriesto A. Shurrush
The Wohl Drug Discovery Institute of the Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 7610001, Israel
Yael Elbaz-Alon
Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
Nadav Scher
Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
Emilie Giraud
Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Chemogenomic and Biological Screening Core Facility, C2RT, Paris, France
Jaouen Tran-Rajau
Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Chemogenomic and Biological Screening Core Facility, C2RT, Paris, France
Fabrice Agou
Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Chemogenomic and Biological Screening Core Facility, C2RT, Paris, France
Haim Michael Barr
The Wohl Drug Discovery Institute of the Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot 7610001, Israel
Ori Avinoam
Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel; Corresponding author
Summary: The COVID-19 pandemic highlighted the need for antivirals against emerging coronaviruses (CoV). Inhibiting spike (S) glycoprotein-mediated viral entry is a promising strategy. To identify small molecule inhibitors that block entry downstream of receptor binding, we established a high-throughput screening (HTS) platform based on pseudoviruses. We employed a three-step process to screen nearly 200,000 small molecules. First, we identified hits that inhibit pseudoviruses bearing the SARS-CoV-2 S glycoprotein. Counter-screening against pseudoviruses with the vesicular stomatitis virus glycoprotein (VSV-G), yielded sixty-five SARS-CoV-2 S-specific inhibitors. These were further tested against pseudoviruses bearing the MERS-CoV S glycoprotein, which uses a different receptor. Out of these, five compounds, which included the known broad-spectrum inhibitor Nafamostat, were subjected to further validation and tested against pseudoviruses bearing the S glycoprotein of the Alpha, Delta, and Omicron variants as well as bona fide SARS-CoV-2. This rigorous approach revealed an unreported inhibitor and its derivative as potential broad-spectrum antivirals.
