On Oct. 11, 2022, researchers from the University of Oxford have reported new findings from a Phase 1 clinical trial studying the safety and immune response of an intranasally-administered vaccine against COVID-19.

The study was performed at the University in collaboration with AstraZeneca and used the same vaccine based on the ChAdOx1 adenovirus vector, as is already licensed for use by injection.

In their findings (published in eBioMedicine), the researchers reported mucosal antibody responses were seen in a minority of participants. Systemic immune responses to intranasal vaccination were also weaker compared with intramuscular vaccination. Therefore, the vaccine did not generate a consistent mucosal antibody nor a strong systemic immune response.

The new Oxford study is thought to be the first to have published data from administration of an adenovirus-vectored vaccine using a simple nasal spray, which might be a more practical option for large-scale vaccine campaigns than a more complex nebuliser device – such as that used by a COVID-19 vaccine recently licensed in China – say the researchers.

For this study, researchers wanted to use exactly the same vaccine as the Oxford-AstraZeneca one to facilitate rapid rollout if the results were positive.