Immunogenicity and In vivo protection of a variant nanoparticle vaccine that confers broad protection against emerging SARS-CoV-2 variants

Logue, J.; Johnson, R.; Patel, N.; Zhou, B.; Maciejewski, S.; Zhou, H.; Portnoff, A.; Tian, J.-H.; McGrath, M.; Haupt, R.; Weston, S.; Hammod, H.; Guebre-Xabier, M.; Dillen, C.; Plested, J.; Cloney-Clark, S.; Greene, A.; Massare, M.; Glenn, G.; Smith, G.; Frieman, M.

doi:10.1101/2021.06.08.447631

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bioRxiv · 10.1101/2021.06.08.447631

Immunogenicity and In vivo protection of a variant nanoparticle vaccine that confers broad protection against emerging SARS-CoV-2 variants

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Abstract

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to spread globally. As SARS-CoV-2 has transmitted from person to person, variant viruses have emerged with elevated transmission rates and higher risk of infection for vaccinees. We present data showing that a recombinant prefusion-stabilized Spike (rS) protein based on the B.1.351 sequence (rS-B.1.351) was highly immunogenic in mice and produced neutralizing antibodies against SARS-CoV-2/WA1, B.1.1.7, and B.1.351. Mice vaccinated with our prototype vaccine NVX-CoV2373 (rS-WU1) or rS-B.1.351 alone, in combination, or as a heterologous prime boost, were protected when challenged with live SARS-CoV-2/B.1.1.7 or SARS-CoV-2/B.1.351. Virus titer was reduced to undetectable levels in the lungs post-challenge in all vaccinated mice, and Th1-skewed cellular responses were observed. A strong anamnestic response was demonstrated in baboons boosted with rS-B.1.351 approximately one year after immunization with NVX-CoV2373 (rS-WU1). An rS-B.1.351 vaccine alone or in combination with prototype rS-WU1 induced protective antibody- and cell-mediated responses that were protective against challenge with SARS-CoV-2 variant viruses.

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Logue, J., Johnson, R., Patel, N., Zhou, B., Maciejewski, S., Zhou, H., Portnoff, A., Tian, J.-H., McGrath, M., Haupt, R., Weston, S., Hammod, H., Guebre-Xabier, M., Dillen, C., Plested, J., Cloney-Clark, S., Greene, A., Massare, M., Glenn, G., Smith, G., Frieman, M.. 2021-06-09. Immunogenicity and In vivo protection of a variant nanoparticle vaccine that confers broad protection against emerging SARS-CoV-2 variants. https://doi.org/10.1101/2021.06.08.447631

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