Arsenal of Nanobodies for Broad-Spectrum Countermeasures against Current and Future SARS-CoV-2 Variants of Concerns

Rossotti, M. A.; van Faassen, H.; Tran, A.; Sheff, J.; Sandhu, J. A.; Duque, D.; Hewitt, M.; Wen, S.; Bavananthasivam, R.; Beitari, S.; Matte, K.; Laroche, G.; Giguere, P. M.; Gervais, C.; Stuible, M.; Guimond, J.; Perret, S.; Hussack, G.; Langlois, M.-A.; Durocher, Y.; Tanha, J.

doi:10.1101/2021.12.20.473401

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bioRxiv · 10.1101/2021.12.20.473401

Arsenal of Nanobodies for Broad-Spectrum Countermeasures against Current and Future SARS-CoV-2 Variants of Concerns

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Abstract

Nanobodies offer several potential advantages over mAbs for the control of SARS-CoV-2. Their ability to access cryptic epitopes conserved across SARS-CoV-2 variants of concern (VoCs) and feasibility to engineer modular, multimeric designs, make these antibody fragments ideal candidates for developing broad-spectrum therapeutics against current and continually emerging SARS-CoV-2 VoCs. Here we describe a diverse collection of 37 anti-SARS-CoV-2 spike glycoprotein nanobodies extensively characterized as both monovalent and IgG Fc-fused bivalent modalities. The panel of nanobodies were shown to have high intrinsic affinity; high thermal, thermodynamic and aerosolization stability; broad subunit/domain specificity and cross-reactivity across many VoCs; wide-ranging epitopic and mechanistic diversity; high and broad in vitro neutralization potencies; and high neutralization efficacies in hamster models of SARS-CoV-2 infection, reducing viral burden by up to six orders of magnitude to below detectable levels. In vivo protection was demonstrated with anti-RBD and previously unreported anti-NTD and anti-S2 nanobodies. This collection of nanobodies provides a therapeutic toolbox from which various cocktails or multi-paratopic formats could be built to tackle current and future SARS-CoV-2 variants and SARS-related viruses. Furthermore, the high aerosol-ability of nanobodies provides the option for effective needle-free delivery through inhalation.

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Rossotti, M. A., van Faassen, H., Tran, A., Sheff, J., Sandhu, J. A., Duque, D., Hewitt, M., Wen, S., Bavananthasivam, R., Beitari, S., Matte, K., Laroche, G., Giguere, P. M., Gervais, C., Stuible, M., Guimond, J., Perret, S., Hussack, G., Langlois, M.-A., Durocher, Y., Tanha, J.. 2021-12-21. Arsenal of Nanobodies for Broad-Spectrum Countermeasures against Current and Future SARS-CoV-2 Variants of Concerns. https://doi.org/10.1101/2021.12.20.473401

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