Single-dose replicating RNA vaccine induces neutralizing antibodies against SARS-CoV-2 in nonhuman primates

Erasmus, J. H.; Khandhar, A. P.; Walls, A. C.; Hemann, E. A.; O'Connor, M. A.; Murapa, P.; Archer, J.; Leventhal, S.; Fuller, J.; Lewis, T.; Draves, K. E.; Randall, S.; Guerriero, K. A.; Duthie, M. S.; Carter, D.; Reed, S. G.; Hawman, D. W.; Feldmann, H.; Gale, M.; Veesler, D.; Berglund, P.; Fuller, D. H.

doi:10.1101/2020.05.28.121640

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bioRxiv · 10.1101/2020.05.28.121640

Single-dose replicating RNA vaccine induces neutralizing antibodies against SARS-CoV-2 in nonhuman primates

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Abstract

The ongoing COVID-19 pandemic, caused by infection with SARS-CoV-2, is having a dramatic and deleterious impact on health services and the global economy. Grim public health statistics highlight the need for vaccines that can rapidly confer protection after a single dose and be manufactured using components suitable for scale-up and efficient distribution. In response, we have rapidly developed repRNA-CoV2S, a stable and highly immunogenic vaccine candidate comprised of an RNA replicon formulated with a novel Lipid InOrganic Nanoparticle (LION) designed to enhance vaccine stability, delivery and immunogenicity. We show that intramuscular injection of LION/repRNA-CoV2S elicits robust anti-SARS-CoV-2 spike protein IgG antibody isotypes indicative of a Type 1 T helper response as well as potent T cell responses in mice. Importantly, a single-dose administration in nonhuman primates elicited antibody responses that potently neutralized SARS-CoV-2. These data support further development of LION/repRNA-CoV2S as a vaccine candidate for prophylactic protection from SARS-CoV-2 infection.

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Erasmus, J. H., Khandhar, A. P., Walls, A. C., Hemann, E. A., O'Connor, M. A., Murapa, P., Archer, J., Leventhal, S., Fuller, J., Lewis, T., Draves, K. E., Randall, S., Guerriero, K. A., Duthie, M. S., Carter, D., Reed, S. G., Hawman, D. W., Feldmann, H., Gale, M., Veesler, D., Berglund, P., Fuller, D. H.. 2020-05-28. Single-dose replicating RNA vaccine induces neutralizing antibodies against SARS-CoV-2 in nonhuman primates. https://doi.org/10.1101/2020.05.28.121640

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