Evaluation of the immunogenicity of prime-boost vaccination with the replication-deficient viral vectored COVID-19 vaccine candidate ChAdOx1 nCoV-19

Graham, S. P.; McLean, R. K.; Spencer, A. J.; Belij-Rammerstorfer, S.; Wright, D.; Ulaszewska, M.; Edwards, J. C.; Hayes, J. W. P.; Martini, V.; Thakur, N.; Conceicao, C.; Dietrich, I.; Shelton, H.; Waters, R.; Ludi, A.; Wilsden, G.; Browning, C.; Bialy, D.; Bhat, S.; Stevenson-Leggett, P.; Hollinghurst, P.; Gilbride, C.; Pulido, D.; Moffat, K.; Sharpe, H.; Allen, E.; Mioulet, V.; Chiu, C.; Newman, J.; Asfor, A. S.; Burman, A.; Crossley, S.; Huo, J.; Owens, R. J.; Carroll, M.; Hammond, J. A.; Tchilian, E.; Bailey, D.; Charleston, B.; Gilbert, S. C.; Tuthill, T. J.; Lambe, T.

doi:10.1101/2020.06.20.159715

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bioRxiv · 10.1101/2020.06.20.159715

Evaluation of the immunogenicity of prime-boost vaccination with the replication-deficient viral vectored COVID-19 vaccine candidate ChAdOx1 nCoV-19

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Abstract

Clinical development of the COVID-19 vaccine candidate ChAdOx1 nCoV-19, a replication-deficient simian adenoviral vector expressing the full-length SARS-CoV-2 spike (S) protein was initiated in April 2020 following non-human primate studies using a single immunisation. Here, we compared the immunogenicity of one or two doses of ChAdOx1 nCoV-19 in both mice and pigs. Whilst a single dose induced antigen-specific antibody and T cells responses, a booster immunisation enhanced antibody responses, particularly in pigs, with a significant increase in SARS-CoV-2 neutralising titres.

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Graham, S. P., McLean, R. K., Spencer, A. J., Belij-Rammerstorfer, S., Wright, D., Ulaszewska, M., Edwards, J. C., Hayes, J. W. P., Martini, V., Thakur, N., Conceicao, C., Dietrich, I., Shelton, H., Waters, R., Ludi, A., Wilsden, G., Browning, C., Bialy, D., Bhat, S., Stevenson-Leggett, P., Hollinghurst, P., Gilbride, C., Pulido, D., Moffat, K., Sharpe, H., Allen, E., Mioulet, V., Chiu, C., Newman, J., Asfor, A. S., Burman, A., Crossley, S., Huo, J., Owens, R. J., Carroll, M., Hammond, J. A., Tchilian, E., Bailey, D., Charleston, B., Gilbert, S. C., Tuthill, T. J., Lambe, T.. 2020-06-20. Evaluation of the immunogenicity of prime-boost vaccination with the replication-deficient viral vectored COVID-19 vaccine candidate ChAdOx1 nCoV-19. https://doi.org/10.1101/2020.06.20.159715

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