ChAdOx1 nCoV-19 (AZD1222) vaccine candidate significantly reduces SARS-CoV-2 shedding in ferrets.
Marsh GA., McAuley AJ., Au GG., Riddell S., Layton D., Singanallur NB., Layton R., Payne J., Durr PA., Bender H., Barr JA., Bingham J., Boyd V., Brown S., Bruce MP., Burkett K., Eastwood T., Edwards S., Gough T., Halpin K., Harper J., Holmes C., Horman WSJ., van Vuren PJ., Lowther S., Maynard K., McAuley KD., Neave MJ., Poole T., Rootes C., Rowe B., Soldani E., Stevens V., Stewart CR., Suen WW., Tachedjian M., Todd S., Trinidad L., Walter D., Watson N., Drew TW., Gilbert SC., Lambe T., Vasan SS.
Vaccines against SARS-CoV-2 are likely to be critical in the management of the ongoing pandemic. A number of candidates are in Phase III human clinical trials, including ChAdOx1 nCoV-19 (AZD1222), a replication-deficient chimpanzee adenovirus-vectored vaccine candidate. In preclinical trials, the efficacy of ChAdOx1 nCoV-19 against SARS-CoV-2 challenge was evaluated in a ferret model of infection. Groups of ferrets received either prime-only or prime-boost administration of ChAdOx1 nCoV-19 via the intramuscular or intranasal route. All ChAdOx1 nCoV-19 administration combinations resulted in significant reductions in viral loads in nasal-wash and oral swab samples. No vaccine-associated adverse events were observed associated with the ChAdOx1 nCoV-19 candidate, with the data from this study suggesting it could be an effective and safe vaccine against COVID-19. Our study also indicates the potential for intranasal administration as a way to further improve the efficacy of this leading vaccine candidate.