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bioRxiv · 10.1101/2022.11.29.518404

Virus-like particle displaying SARS-CoV-2 receptor binding domain elicits neutralizing antibodies and is protective in a challenge model

McKechnie, J. L.·Fiala, B.·Wolf, C.·Ellis, D.·Holtzman, D.·Feldhaus, A.
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Abstract

While the effort to vaccinate people against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has largely been successful, particularly in the developed world, the rise of new variants as well as waning immunity illustrate the need for a new generation of vaccines that provide broader and/or more durable protection against infection and severe disease. Here we describe the generation and characterization of IVX-411, a computationally designed, two-component virus-like particle (VLP) displaying the ancestral SARS-CoV-2 receptor binding domain (RBD) on its surface. Immunization of mice with IVX-411 generates neutralizing antibodies against the ancestral strain as well as three variants of concern. Neutralizing antibody titers elicited by IVX-411 are durable and significantly higher than those elicited by immunization with soluble RBD and spike antigens. Furthermore, immunization with IVX-411 is shown to be protective in a Syrian Golden hamster challenge model using two different strains of SARS-CoV-2. Overall, these studies demonstrate that IVX-411 is highly immunogenic and capable of eliciting broad, protective immunity.

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McKechnie, J. L., Fiala, B., Wolf, C., Ellis, D., Holtzman, D., Feldhaus, A.. 2022-11-29. Virus-like particle displaying SARS-CoV-2 receptor binding domain elicits neutralizing antibodies and is protective in a challenge model. https://doi.org/10.1101/2022.11.29.518404

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