Ontario university researchers say they are working on a DNA-based COVID-19 nasal vaccine.
University of Waterloo School of Pharmacy Prof. Roderick Slavcev said the vaccine would work by using bacteriophage, a process allowing the vaccine to replicate within bacteria already in the body. It is being designed to target tissues in the nasal cavity and lower respiratory tract, he said.
“When complete, our DNA-based vaccine will be administered non-invasively as a nasal spray that delivers nanomedicine engineered to immunize and decrease COVID-19 infections,” said Slavcev, who specializes in designing vaccines, pharmaceuticals and gene-therapy treatments.
“This research combines the expertise of many and leverages existing technology developed by my team, which we’re reconfiguring for a COVID-19 application,” he said.
The research team’s aim is to have the vaccine enter cells in targeted tissues and cause them to produce a virus-like particle – or VLP - to stimulate an immune response.
Slavcev explained the VLP will look similar to the structure of SARS-CoV-2 (the virus which causes COVID-19), but is harmless.
It’s that similarity that would activate the body’s natural immune response to protect against viral infections comparable to the VLP, including SARS-CoV-2,” he said.
Further, it would also bind to receptors that SARS-CoV-2 would bind to, limiting the possible sites for transmission.
By causing these changes in the body, the vaccine would build immunity against COVID-19 and decrease the severity of infections in progress.
That means it would serve as both a therapeutic and a vaccine, Slavcev said.
“Every detail of the vaccine, from ensuring the bacteriophage target specific cells in the respiratory tract to creating a minimal VLP to impersonate SARS-CoV-2, is specifically engineered by the researchers and requires testing,” the university said in a news release.
Multiple research teams globally are working on vaccines with availability estimates reaching up to 18 months.
COVID-19 drugs trials led by a UBC researcher were due to start last week in multiple European locations. Prof Josef Penninger’s team said it had found a trial drug that blocks the cellular door the virus uses to infect people with COVID-19.
The Waterloo work is a multi-disciplinary collaboration between Slavcev, fellow pharmacy professor Emmanuel Ho and chemical engineering professor Marc Aucoin.
Ho’s team is designing the nanomedication that will be delivered by the nasal spray, which is currently being tested, while Aucoin’s lab is constructing and purifying the VLP and boosting immunity following the initial administration of the therapeutic vaccine.
Slavcev’s team has completed design of the bacteriophage delivery system and is now modifying it to apply to COVID-19.
Additional design of components and further testing will take place later this year.
The university stressed the research has not yet been peer-reviewed with the information being released as part of its commitment to help inform Canada’s COVID-19 response.
Research components are supported by a grant from the Natural Sciences and Engineering Research Council of Canada.