One mucosal administration of a live attenuated recombinant COVID-19 vaccine protects non-human primates from SARS-CoV-2

Tioni, M. F.; Jordan, R.; Silva Pena, A.; Garg, A.; Wu, D.; Phan, S. I.; Cheng, X.; Greenhouse, J.; Orekov, T.; Valentin, D.; Kar, S.; Pessaint, L.; Andersen, H.; Stobart, C. C.; Bloodworth, M. H.; Peebles, R. S.; Liu, Y.; Xie, X.; Shi, P.-Y.; Moore, M. L.; Tang, R. S.

doi:10.1101/2021.07.16.452733

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bioRxiv · 10.1101/2021.07.16.452733

One mucosal administration of a live attenuated recombinant COVID-19 vaccine protects non-human primates from SARS-CoV-2

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Abstract

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 global pandemic. SARS-CoV-2 is an enveloped RNA virus that relies on its trimeric surface glycoprotein, spike, for entry into host cells. Here we describe the COVID-19 vaccine candidate MV-014-212, a live attenuated, recombinant human respiratory syncytial virus (RSV) expressing a chimeric SARS-CoV-2 spike as the only viral envelope protein. MV-014-212 was attenuated and immunogenic in African green monkeys (AGMs). One mucosal administration of MV-014-212 in AGMs protected against SARS-CoV-2 challenge, reducing by more than 200- fold the peak shedding of SARS-CoV-2 in the nose. MV-014-212 elicited mucosal immunity in the nose and neutralizing antibodies in serum that exhibited cross-neutralization against two virus variants of concern. Intranasally delivered, live attenuated vaccines such as MV-014-212 entail low-cost manufacturing suitable for global deployment. MV-014-212 is currently in phase 1 clinical trials as a single-dose intranasal COVID-19 vaccine.

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Tioni, M. F., Jordan, R., Silva Pena, A., Garg, A., Wu, D., Phan, S. I., Cheng, X., Greenhouse, J., Orekov, T., Valentin, D., Kar, S., Pessaint, L., Andersen, H., Stobart, C. C., Bloodworth, M. H., Peebles, R. S., Liu, Y., Xie, X., Shi, P.-Y., Moore, M. L., Tang, R. S.. 2021-07-19. One mucosal administration of a live attenuated recombinant COVID-19 vaccine protects non-human primates from SARS-CoV-2. https://doi.org/10.1101/2021.07.16.452733

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