PRE-CLINICAL IMMUNE RESPONSE AND SAFETY EVALUATION OF THE PROTEIN SUBUNIT VACCINE NANOCOVAX FOR COVID-19

Tran, T. N. M.; May, B.; Ung, T. T.; Nguyen, M. K.; Nguyen, T. T.; Dinh, V. L.; Tran, T. V.; Khong, H.; Hua, H. Q. H.; Nguyen, V. A.; Ha, T. P.; Phan, D. L.; Nguyen, T. A.; Bui, T. N.; Tu, T. M.; Le, T. H.; Dong, T. L.; Huynh, T. H.; Truong, C. T.; Nie, L.; Cao, M. N.; Nguyen, D. K.; Trinh, T. H.; Do, M. S.

doi:10.1101/2021.07.20.453162

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bioRxiv · 10.1101/2021.07.20.453162

PRE-CLINICAL IMMUNE RESPONSE AND SAFETY EVALUATION OF THE PROTEIN SUBUNIT VACCINE NANOCOVAX FOR COVID-19

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Abstract

The Coronavirus disease-2019 (COVID-19) pandemic caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), has become a dire global health concern. The development of vaccines with high immunogenicity and safety is crucial for control of the global COVID-19 pandemic and prevention of further illness and fatalities. Here, we report development of SARS-CoV-2 vaccine candidate, Nanocovax, based on recombinant protein production of the extracellular (soluble) portion of the S protein of SARS-CoV-2. The results showed that Nanocovax induced high levels of S protein-specific IgG, as well neutralizing antibody in three animal models including Balb/C mice, Syrian hamsters, and non-human primate (Macaca leonina). In addition, the viral challenge study using the hamster model showed that Nanocovax protected the upper respiratory tract from SARS-CoV-2 infection. No adverse effects were induced by Nanocovax in swiss mice (Musmusculus var. Albino), Rats (Rattus norvegicus), and New Zealand rabbits. These pre-clinical results indicated that Nanocovax is safe and effective.

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Tran, T. N. M., May, B., Ung, T. T., Nguyen, M. K., Nguyen, T. T., Dinh, V. L., Tran, T. V., Khong, H., Hua, H. Q. H., Nguyen, V. A., Ha, T. P., Phan, D. L., Nguyen, T. A., Bui, T. N., Tu, T. M., Le, T. H., Dong, T. L., Huynh, T. H., Truong, C. T., Nie, L., Cao, M. N., Nguyen, D. K., Trinh, T. H., Do, M. S.. 2021-07-21. PRE-CLINICAL IMMUNE RESPONSE AND SAFETY EVALUATION OF THE PROTEIN SUBUNIT VACCINE NANOCOVAX FOR COVID-19. https://doi.org/10.1101/2021.07.20.453162

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