Recombinant Fc-fusion vaccine of RBD induced protection against SARS-CoV-2 in non-human primate and mice

Sun, Y.; Han, G.; Wei, W.; Hu, Z.; Sun, S.; He, L.; Zhao, Z.; Gu, H.; Wang, T.; Yang, X.; Chen, S.; Deng, Y.; Li, J.; Zhao, J.; Li, L.; Li, X.; He, P.; Li, G.; Li, H.; Gao, C.; Lang, X.; Geng, S.; Wang, X.; Fei, G.; Li, Y.; Gao, Y.; Fang, X.; Zhao, Y.

doi:10.1101/2020.11.29.402339

bioRxiv · 10.1101/2020.11.29.402339

Recombinant Fc-fusion vaccine of RBD induced protection against SARS-CoV-2 in non-human primate and mice

Sun, Y.·Han, G.·Wei, W.·Hu, Z.·Sun, S.·He, L.·Zhao, Z.·Gu, H.·Wang, T.·Yang, X.·Chen, S.·Deng, Y.·Li, J.·Zhao, J.·Li, L.·Li, X.·He, P.·Li, G.·Li, H.·Gao, C.·Lang, X.·Geng, S.·Wang, X.·Fei, G.·Li, Y.·Gao, Y.·Fang, X.·Zhao, Y.

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Abstract

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to infect people globally. The increased COVID-19 cases and no licensed vaccines highlight the need to develop safe and effective vaccines against SARS-CoV-2 infection. Multiple vaccines candidates are under pre-clinical or clinical trails with different strengths and weaknesses. Here we developed a pilot scale production of a recombinant subunit vaccine (RBD-Fc Vacc) with the Receptor Binding Domain of SARS-CoV-2 S protein fused with the Fc domain of human IgG1. RBD-Fc Vacc induced SARS-CoV-2 specific neutralizing antibodies in non-human primates and human ACE2 transgenic mice. The antibodies induced in macaca fascicularis neutralized three divergent SARS-CoV2 strains, suggesting a broader neutralizing ability. Three times immunizations protected Macaca fascicularis (20ug or 40ug per dose) and mice (10ug or 20ug per dose) from SARS-CoV-2 infection respectively. These data support clinical development of SARS-CoV-2 vaccines for humans. RBD-Fc Vacc is currently being assessed in randomized controlled phase 1/II human clinical trails. SummaryThis study confirms protective efficacy of a SARS-CoV-2 RBD-Fc subunit vaccine.

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Sun, Y., Han, G., Wei, W., Hu, Z., Sun, S., He, L., Zhao, Z., Gu, H., Wang, T., Yang, X., Chen, S., Deng, Y., Li, J., Zhao, J., Li, L., Li, X., He, P., Li, G., Li, H., Gao, C., Lang, X., Geng, S., Wang, X., Fei, G., Li, Y., Gao, Y., Fang, X., Zhao, Y.. 2020-11-30. Recombinant Fc-fusion vaccine of RBD induced protection against SARS-CoV-2 in non-human primate and mice. https://doi.org/10.1101/2020.11.29.402339

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