Oral and intranasal Ad5 SARS-CoV-2 vaccines decrease disease and viral transmission in a golden hamster model

Langel, S. N.; Johnson, S.; Martinez, C. I.; Tedjakusuma, S. N.; Peinovich, N.; Dora, E. G.; Kuehl, P. J.; Irshad, H.; Barrett, E. G.; Werts, A.; Tucker, S. N.

doi:10.1101/2021.10.03.462919

bioRxiv · 10.1101/2021.10.03.462919

Oral and intranasal Ad5 SARS-CoV-2 vaccines decrease disease and viral transmission in a golden hamster model

Langel, S. N.·Johnson, S.·Martinez, C. I.·Tedjakusuma, S. N.·Peinovich, N.·Dora, E. G.·Kuehl, P. J.·Irshad, H.·Barrett, E. G.·Werts, A.·Tucker, S. N.

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Abstract

Transmission-blocking strategies that slow the spread of SARS-CoV-2 and protect against COVID-19 are needed. We have developed a shelf-stable, orally-delivered Ad5-vectored SARS-CoV-2 vaccine candidate that expresses the spike protein. Here we demonstrated that oral and intranasal SARS-CoV-2 vaccination of this candidate protected against disease in index hamsters, and decreased aerosol transmission to unvaccinated, naive hamsters. We confirmed that mucosally-vaccinated hamsters had robust antibody responses. We then induced a post-vaccination infection by inoculating vaccinated index hamsters with SARS-CoV-2. Oral and IN-vaccinated hamsters had decreased viral RNA and infectious virus in the nose and lungs and experienced less lung pathology compared to mock-vaccinated hamsters post challenge. Naive hamsters exposed in a unidirectional air flow chamber to mucosally-vaccinated, SARS-CoV-2-infected hamsters had lower nasal swab viral RNA and exhibited less clinical symptoms of disease than control animals. Our data demonstrate that oral immunization is a viable strategy to decrease SARS-CoV-2 disease and aerosol transmission.

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Langel, S. N., Johnson, S., Martinez, C. I., Tedjakusuma, S. N., Peinovich, N., Dora, E. G., Kuehl, P. J., Irshad, H., Barrett, E. G., Werts, A., Tucker, S. N.. 2021-10-05. Oral and intranasal Ad5 SARS-CoV-2 vaccines decrease disease and viral transmission in a golden hamster model. https://doi.org/10.1101/2021.10.03.462919

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