University of Guelph

Purpose

The University of Guelph developed a vaccine to protect against the novel coronavirus disease that emerged in 2019 (COVID-19) using a safe vector known as avian orthoavulavirus-1 (AOaV-1) with a transgene encoding the full-length spike protein (FLS) from severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). In a hamster challenge model of COVID-19, intranasal vaccination with AOaV-1-FLS completely protected against disease, and SARS-CoV-2 could not be detected. This correlated with the induction of a SARS-CoV-2-specific immune responses in the lungs. The next step requires that this vaccine be optimized for administration into the respiratory system of humans. Specifically, the vaccine vector needs to be adapted to function across a broad range of temperatures, including the relatively low temperature of the nasal passages and the higher temperatures in the lungs. Also, intranasal versus aerosol delivery into the respiratory system will be tested to determine if nasal and/or respiratory delivery induces protective immune responses. In parallel, a next-generation version of the vaccine that expresses a prefusion stabilized SARS-CoV-2 spike protein will be engineered and tested in mice and hamster COVID-19 challenge models. This research will pave the way toward a human clinical trial.