Scientists at McMaster University are set to begin human trials for two brand new inhaled COVID-19 vaccines that are designed to combat variants of concern.
Both “next-generation” vaccines will be delivered by inhaled aerosol, which targets where respiratory infections begin, in the lungs and upper airways.
Researchers in Hamilton will soon test the safety and immune potency of the vaccines during the first phase of clinical trials recently given approval by Health Canada.
Each is designed as a booster and will be given to 30 study participants who have previously received two doses of a COVID mRNA vaccine, such as BioNTech Pfizer or Moderna.
The McMaster vaccines are designed to target parts of the SARS-CoV-2 virus that do not change or mutate. Activating the immune system against three different proteins, rather than one, should provide better protection against variants of concern, the researchers say.
As the pandemic transitions into an endemic infection, researchers around the world have been racing to speed the development of more efficient, broadly applicable vaccines to follow the first generation of emergency vaccines that were designed to stem the initial spread of COVID-19.
“It is critical to continue research on new forms of Covid vaccines that work in a different way and could be used to boost immunity in people who have already been vaccinated,” said Fiona Smaill, a professor of Pathology and Molecular Medicine at McMaster who is leading the clinical trial, in the university’s press release. “By targeting a breadth of immune responses to different parts of the Covid virus, we expect to see broader protection.”
Researchers from @MacGlobalNexus will soon start human trials on two vaccines that are designed to protect against COVID-19 variants of concern and will be delivered straight to the lungs by inhaled aerosol. | @machealthsci https://t.co/dqDznNOk1p pic.twitter.com/QYNGU5PNjo
— McMaster University (@McMasterU) December 7, 2021
The inhaled delivery concept draws on 20 years of research and development on a tuberculosis vaccine led by Zhou Xing, professor in the Department of Medicine and McMaster Immunology Research Centre.
“Besides its multi-antigenic vaccine design, our vaccine strategy differs from all of the current first-generation Covid-19 vaccines. Ours gets delivered into the lung via inhaled aerosol to induce respiratory mucosal immunity, known to provide best protection against respiratory pathogens,” Xing says.
Researchers will examine how the immune response develops in the lungs and blood after vaccination and monitor for possible side effects. They are comparing two strains of weakened adenovirus as platforms for the vaccines: one is made with a human adenovirus, the other a chimpanzee adenovirus.
In their natural form, adenoviruses cause respiratory infections such as the common cold, and in rare cases can cause a lung infection such as pneumonia. In their weakened form, they do not spread disease but can be customized to serve as vehicles, or vectors, to trigger targeted immune responses.
“McMaster has a very long and illustrious history in the study of adenoviruses. This human trial builds on that pioneering work, and… will also advance our fundamental understanding of how to use these viruses most effectively as vaccine vectors,” said Matthew Miller, an associate professor with McMaster’s Michael G. DeGroote Institute for Infectious Disease Research and co-principal investigator.
The vaccines were produced at McMaster’s Robert E. Fitzhenry Vector Laboratory, which is part of McMaster’s Global Nexus for Pandemics and Biological Threats.
“The Fitzhenry Vector lab is a unique resource which made it possible for our team to take innovative research all the way from concept to manufactured vials of vaccine available to boost human volunteers,” added Brian Lichty, an associate professor in the Department of Medicine who is co-leading the vaccine development.
If the first phase is successful, the team has manufactured sufficient vaccine doses to move forward with much larger clinical trials.
