immune memory cells and antibodies in the nose and throat. The study appeared on bioRxiv, a pre-print site for cutting-edge science that has not yet been peer-reviewed.
“Improving upon current vaccine platforms to provide mucosal immunity is important to curb this current pandemic, and certainly will be important to combat the next,” the Yale team wrote.
But the McMaster researchers think their vaccine has another added benefit: it promotes an antibody response against three different parts of the COVID coronavirus, making it more likely that immunity would be longer-lasting than current vaccines that only target the virus’ spike protein.
“While targeting the spike protein made a lot of sense for first-generation vaccines, that approach was going to be inherently limited because this was a virus that was going to continue to evolve. The spike protein was going to mutate and inevitably those vaccines were going to need to be updated,” Miller says.
The Canadian vaccine targets the spike protein, which is the part of the virus that helps it infect cells. However, it also produces an immune response against parts of the virus that protect its genetics and help it replicate — targets that are hidden inside the virus until after it infects a cell, and therefore less likely to mutate away from a vaccine, Miller shares.
Miller said his team is working to get their inhaled vaccine approved under an accelerated timeline, possibly within two years.
“I do think inhaled vaccines will be that next major innovation in vaccine design, and hold the promise of really improving the protectiveness of vaccines for respiratory pathogens, including things like influenza for which our current seasonal vaccines are far short of optimal in terms of the average vaccine effectiveness we see on a yearly basis,” Miller adds.
The McMaster vaccine research was published online Feb. 8 in the journal Cell.
Other research teams don’t plan to stop with COVID.
Casper says inhaled vaccines make a lot of sense for other respiratory infections, including influenza, RSV and tuberculosis.
“The number one infectious disease killer around the world is still tuberculosis — not incredibly common in the United States, but more people are dying of tuberculosis than any other infectious disease on the planet,” Casper notes. “There’s really good evidence to suggest that inhaled vaccines, whether it be in the lung or in the nose, would be highly effective against tuberculosis.”
The U.S. Centers for Disease Control and Prevention has more about COVID-19 vaccines.