Highly potent anti-SARS-CoV-2 multi-DARPin therapeutic candidates

Walser, Marcel; Rothenberger, Sylvia; Hurdiss, Daniel L.; Schlegel, Anja; Calabro, Valerie; Fontaine, Simon; Villemagne, Denis; Paladino, Maria; Hospodarsch, Tanja; Neculcea, Alexandra; Cornelius, Andreas; Schildknecht, Patricia; Matzner, Mirela; Haenggi, Martin; Franchini, Marco; Kaufmann, Yvonne; Schaible, Doris; Schlegel, Iris; Iss, Chloe; Looser, Thamar; Mangold, Susanne; Herzog, Christel; Schiegg, Dieter; Reichen, Christian; Radom, Filip; Bosshart, Andreas; Lehmann, Andreas; Haeuptle, Micha A.; Zuercher, Alexander; Vagt, Toni; Sigrist, Gabriel; Straumann, Marcel; Proba, Karl; Veitonmaki, Niina; Dawson, Keith M.; Zitt, Christof; Mayor, Jennifer; Ryter, Sarah; Lyoo, Heyrhyoung; Wang, Chunyan; Li, Wentao; Drulyte, Ieva; Du, Wenjuan; Binz, H. Kaspar; Waal, Leon de; Stittelaar, Koert J.; Taplin, Sarah; Lewis, Seth; Steiner, Daniel; Kuppeveld, Frank J.M. van; Engler, Olivier; Bosch, Berend-Jan; Stumpp, Michael T.; Amstutz, Patrick

Globally accessible therapeutics against SARS-CoV-2 are urgently needed. Here, we report the generation of the first anti-SARS-CoV-2 DARPin molecules with therapeutic potential as well as rapid large-scale production capabilities. Highly potent multi-DARPin molecules with low picomolar virus neutralization efficacies were generated by molecular linkage of three different mono-DARPin molecules. These multi-DARPin molecules target various domains of the SARS-CoV-2 spike protein, thereby limiting possible viral escape. Cryo-EM analysis of individual mono-DARPin molecules provided structural explanations for the mode of action. Analysis of the protective efficacy of one multi-DARPin molecule in a hamster SARS-CoV-2 infection model demonstrated a significant reduction of pathogenesis. Taken together, the multi-DARPin molecules reported here, one of which is currently entering clinical studies, constitute promising therapeutics against the COVID-19 pandemic.