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bioRxiv · 10.1101/2020.07.08.193045

A single-dose live-attenuated YF17D-vectored SARS-CoV2 vaccine candidate

Lorena Sanchez Felipe·Thomas Vercruysse·Sapna Sharma·Ji Ma·Viktor Lemmens·Dominique van Looveren·Mahadesh Prasad Arkalagud Javarappa·Robbert Boudewijns·Bert Malengier-Devlies·Suzanne F. Kaptein·Laurens Liesenborghs·Carolien De Keyzer·Lindsey Bervoets·Madina Rasulova·Laura Seldeslachts·Sander Jansen·Michael Bright Yakass·Osbourne Quaye·Li-Hsin Li·Xin Zhang·Sebastiaan ter Horst·Niraj Mishra·Lotte Coelmont·Christopher Cawthorne·Koen Van Laere·Ghislain Opdenakker·Greetje Van de Velde·Birgit Weynand·Dirk E. Teuwen·Patrick Matthys·Johan Neyts·Hendrik Jan Thibaut·Kai D
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Abstract

The explosively expanding COVID-19 pandemic urges the development of safe, efficacious and fast-acting vaccines to quench the unrestrained spread of SARS-CoV-2. Several promising vaccine platforms, developed in recent years, are leveraged for a rapid emergency response to COVID-191. We employed the live-attenuated yellow fever 17D (YF17D) vaccine as a vector to express the prefusion form of the SARS-CoV-2 Spike antigen. In mice, the vaccine candidate, tentatively named YF-S0, induces high levels of SARS-CoV-2 neutralizing antibodies and a favorable Th1 cell-mediated immune response. In a stringent hamster SARS-CoV-2 challenge model2, vaccine candidate YF-S0 prevents infection with SARS-CoV-2. Moreover, a single dose confers protection from lung disease in most vaccinated animals even within 10 days. These results warrant further development of YF-S0 as a potent SARS-CoV-2 vaccine candidate.

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Lorena Sanchez Felipe, Thomas Vercruysse, Sapna Sharma, Ji Ma, Viktor Lemmens, Dominique van Looveren, Mahadesh Prasad Arkalagud Javarappa, Robbert Boudewijns, Bert Malengier-Devlies, Suzanne F. Kaptein, Laurens Liesenborghs, Carolien De Keyzer, Lindsey Bervoets, Madina Rasulova, Laura Seldeslachts, Sander Jansen, Michael Bright Yakass, Osbourne Quaye, Li-Hsin Li, Xin Zhang, Sebastiaan ter Horst, Niraj Mishra, Lotte Coelmont, Christopher Cawthorne, Koen Van Laere, Ghislain Opdenakker, Greetje Van de Velde, Birgit Weynand, Dirk E. Teuwen, Patrick Matthys, Johan Neyts, Hendrik Jan Thibaut, Kai D. 2020-07-09. A single-dose live-attenuated YF17D-vectored SARS-CoV2 vaccine candidate. https://doi.org/10.1101/2020.07.08.193045

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