A single intranasal dose of chimpanzee adenovirus-vectored vaccine protects against SARS-CoV-2 infection in rhesus macaques

Hassan, A. O.; Feldmann, F.; Zhao, H.; Curiel, D. T.; Okumura, A.; Tang-Huau, T.-L.; Case, J. B.; Meade-White, K.; Callison, J.; Lovaglio, J.; Hanley, P. W.; Scott, D. P.; Fremont, D. H.; Feldmann, H.; Diamond, M. S.

doi:10.1101/2021.01.26.428251

bioRxiv · 10.1101/2021.01.26.428251

A single intranasal dose of chimpanzee adenovirus-vectored vaccine protects against SARS-CoV-2 infection in rhesus macaques

Hassan, A. O.·Feldmann, F.·Zhao, H.·Curiel, D. T.·Okumura, A.·Tang-Huau, T.-L.·Case, J. B.·Meade-White, K.·Callison, J.·Lovaglio, J.·Hanley, P. W.·Scott, D. P.·Fremont, D. H.·Feldmann, H.·Diamond, M. S.

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Abstract

The deployment of a vaccine that limits transmission and disease likely will be required to end the Coronavirus Disease 2019 (COVID-19) pandemic. We recently described the protective activity of an intranasally-administered chimpanzee adenovirus-vectored vaccine encoding a pre-fusion stabilized spike (S) protein (ChAd-SARS-CoV-2-S) in the upper and lower respiratory tract of mice expressing the human angiotensin-converting enzyme 2 (ACE2) receptor. Here, we show the immunogenicity and protective efficacy of this vaccine in non-human primates. Rhesus macaques were immunized with ChAd-Control or ChAd-SARS-CoV-2-S and challenged one month later by combined intranasal and intrabronchial routes with SARS-CoV-2. A single intranasal dose of ChAd-SARS-CoV-2-S induced neutralizing antibodies and T cell responses and limited or prevented infection in the upper and lower respiratory tract after SARS-CoV-2 challenge. As this single intranasal dose vaccine confers protection against SARS-CoV-2 in non-human primates, it is a promising candidate for limiting SARS-CoV-2 infection and transmission in humans.

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Hassan, A. O., Feldmann, F., Zhao, H., Curiel, D. T., Okumura, A., Tang-Huau, T.-L., Case, J. B., Meade-White, K., Callison, J., Lovaglio, J., Hanley, P. W., Scott, D. P., Fremont, D. H., Feldmann, H., Diamond, M. S.. 2021-01-26. A single intranasal dose of chimpanzee adenovirus-vectored vaccine protects against SARS-CoV-2 infection in rhesus macaques. https://doi.org/10.1101/2021.01.26.428251

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