Fourth dose of Microneedle Array Patch of SARS-CoV-2 S1 Protein Subunit Vaccine Elicits Robust Long-lasting Humoral Responses in mice

Kim, E.; Shin, J.; Ferrari, A.; Huang, S.; An, E.; Han, D.; Khan, M. S.; Kenniston, T. W.; Cassaniti, I.; Baldanti, F.; Jeong, D.; Gambotto, A.

doi:10.1101/2023.10.05.561047

bioRxiv · 10.1101/2023.10.05.561047

Fourth dose of Microneedle Array Patch of SARS-CoV-2 S1 Protein Subunit Vaccine Elicits Robust Long-lasting Humoral Responses in mice

Kim, E.·Shin, J.·Ferrari, A.·Huang, S.·An, E.·Han, D.·Khan, M. S.·Kenniston, T. W.·Cassaniti, I.·Baldanti, F.·Jeong, D.·Gambotto, A.

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Abstract

The COVID-19 pandemic has underscored the pressing need for safe and effective booster vaccines, particularly in considering the emergence of new SARS-CoV-2 variants and addressing vaccine distribution inequalities. Dissolving microneedle array patches (MAP) offer a promising delivery method, enhancing immunogenicity and improving accessibility through the skins immune potential. In this study, we evaluated a microneedle array patch-based S1 subunit protein COVID-19 vaccine candidate, which comprised a bivalent formulation targeting the Wuhan and Beta variant alongside a monovalent Delta variant spike proteins in a murine model. Notably, the second boost of homologous bivalent MAP-S1(WU+Beta) induced a 15.7-fold increase in IgG endpoint titer, while the third boost of heterologous MAP-S1RS09Delta yielded a more modest 1.6-fold increase. Importantly, this study demonstrated that the administration of four doses of the MAP vaccine induced robust and long-lasting immune responses, persisting for at least 80 weeks. These immune responses encompassed various IgG isotypes and remained statistically significant for one year. Furthermore, neutralizing antibodies against multiple SARS-CoV-2 variants were generated, with comparable responses observed against the Omicron variant. Overall, these findings emphasize the potential of MAP-based vaccines as a promising strategy to combat the evolving landscape of COVID-19 and to deliver a safe and effective booster vaccine worldwide.

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Kim, E., Shin, J., Ferrari, A., Huang, S., An, E., Han, D., Khan, M. S., Kenniston, T. W., Cassaniti, I., Baldanti, F., Jeong, D., Gambotto, A.. 2023-10-05. Fourth dose of Microneedle Array Patch of SARS-CoV-2 S1 Protein Subunit Vaccine Elicits Robust Long-lasting Humoral Responses in mice. https://doi.org/10.1101/2023.10.05.561047

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