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bioRxiv · 10.1101/2020.11.10.376905

Protective efficacy of a SARS-CoV-2 DNA Vaccine in wild-type and immunosuppressed Syrian hamsters

Brocato, R.·Kwilas, S. A.·Kim, R. K.·Zeng, X.·Principe, L. M.·Smith, J. M.·Hooper, J.
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Abstract

A worldwide effort to counter the COVID-19 pandemic has resulted in hundreds of candidate vaccines moving through various stages of research and development, including several vaccines in phase 1, 2 and 3 clinical trials. A relatively small number of these vaccines have been evaluated in SARS-CoV-2 disease models, and fewer in a severe disease model. Here, a SARS-CoV-2 DNA targeting the spike protein and delivered by jet injection, nCoV-S(JET), elicited neutralizing antibodies in hamsters and was protective in both wild-type and transiently immunosuppressed hamster models. This study highlights the DNA vaccine, nCoV-S(JET), we developed has a great potential to move to next stage of preclinical studies, and it also demonstrates that the transiently-immunosuppressed Syrian hamsters, which recapitulate severe and prolonged COVID-19 disease, can be used for preclinical evaluation of the protective efficacy of spike-based COVID-19 vaccine.

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Brocato, R., Kwilas, S. A., Kim, R. K., Zeng, X., Principe, L. M., Smith, J. M., Hooper, J.. 2020-11-10. Protective efficacy of a SARS-CoV-2 DNA Vaccine in wild-type and immunosuppressed Syrian hamsters. https://doi.org/10.1101/2020.11.10.376905

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