Boosting of SARS-CoV-2 immunity in nonhuman primates using an oral rhabdoviral vaccine

Peng, K. W.; Carey, T.; Lech, P.; Vandergaast, R.; Munoz-Alia, M. A.; Packiriswamy, N.; Gnanadurai, C.; Krotova, K.; Tesfay, M.; Ziegler, C.; Haselton, M.; Sevola, K.; Lathrum, C.; Reiter, S.; Narjari, R.; Balakrishnan, B.; Suksanpaisan, L.; Sakuma, T.; Recker, J.; Zhang, L.; Waniger, S.; Russell, L.; Petro, C.; Kyratsous, C. A.; Baum, A.; Janecek, J. L.; Lee, R.; Ramachandran, S.; Graham, M.; Russell, S. J.

doi:10.1101/2021.10.16.464660

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bioRxiv · 10.1101/2021.10.16.464660

Boosting of SARS-CoV-2 immunity in nonhuman primates using an oral rhabdoviral vaccine

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Abstract

An orally active vaccine capable of boosting SARS-CoV-2 immune responses in previously infected or vaccinated individuals would help efforts to achieve and sustain herd immunity. Unlike mRNA-loaded lipid nanoparticles and recombinant replication-defective adenoviruses, replicating vesicular stomatitis viruses with SARS-CoV-2 spike glycoproteins (VSV-SARS2) were poorly immunogenic after intramuscular administration in clinical trials. Here, by G protein trans-complementation, we generated VSV-SARS2(+G) virions with expanded target cell tropism. Compared to parental VSV-SARS2, G-supplemented viruses were orally active in virus-naive and vaccine-primed cynomolgus macaques, powerfully boosting SARS-CoV-2 neutralizing antibody titers. Clinical testing of this oral VSV-SARS2(+G) vaccine is planned.

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Peng, K. W., Carey, T., Lech, P., Vandergaast, R., Munoz-Alia, M. A., Packiriswamy, N., Gnanadurai, C., Krotova, K., Tesfay, M., Ziegler, C., Haselton, M., Sevola, K., Lathrum, C., Reiter, S., Narjari, R., Balakrishnan, B., Suksanpaisan, L., Sakuma, T., Recker, J., Zhang, L., Waniger, S., Russell, L., Petro, C., Kyratsous, C. A., Baum, A., Janecek, J. L., Lee, R., Ramachandran, S., Graham, M., Russell, S. J.. 2021-10-18. Boosting of SARS-CoV-2 immunity in nonhuman primates using an oral rhabdoviral vaccine. https://doi.org/10.1101/2021.10.16.464660

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