Investing in the future of vaccines
If the COVID-19 pandemic has taught the world anything, it's that without critical medical infrastructure, such as proper refrigeration for vaccines, immunization efforts cannot run smoothly. How can we deliver vaccines to villages with no electricity, high humidity and sub-Saharan temperatures?
“It has really become clear that infectious diseases are increasingly threatening the functioning of our global society—and projections show that within 20 or 30 years, antibiotic resistance will create a COVID-sized global health event every year,” said Reinhard Vehring, professor in the Faculty of Engineering.
Vehring has been working on the problem of stable vaccines for several years. Before the pandemic began, he was working on a shelf-stable, powdered version of a tuberculosis vaccine. However, once COVID-19 became a priority, his lab quickly shifted focus to a coronavirus vaccine thanks to support from the COVID-19 and Emerging Pathogens Fund.
“Vaccinations are arguably the most effective intervention against infectious diseases,” he said. “The problem is that most vaccines need to be refrigerated, and they are almost exclusively given by injection. So to deal with COVID-sized events, now you need two things: you need trained health-care professionals, and you need a functioning health infrastructure, including electricity for refrigeration.”
Vehring’s goal is a vaccine dosage form that can be used anywhere in the world—it needs to be stable at any temperature, able to withstand high humidities, affordable and easy to use. The obvious choice was a powder, but how do you powder a vaccine?
To answer that, Vehring’s team drew inspiration from nature and powdered foods.
“There are plants in Namibia, for example, that can go without water for years; they look completely dead as there's virtually no water in there. But when it rains, they sprout again and turn green,” Vehring said. “Normally when you remove water, proteins will unfold and that's the end of any living being. But these plants synthesize large amounts of a sugar called trehalose, which replaces some of the functions of water and keeps the proteins from unfolding.”
The process begins by spray-drying a vaccine to get fine solid particles, similar to how powdered milk is made. Verhring’s team then packages the vaccine molecules with trehalose and coats them in a crystalline covering to keep the molecules separate and stable. Vehring likens the resulting molecules to M&M candies—soft chocolate candy covered by a hard shell.
“We’ve designed a core shell structure, with the outside very resistant to water and higher temperatures, and inside the sugar and vaccine are nicely protected from the environment,” he said. “So the main message here is that we have found very good tools that allow us to design particles that have a complicated structure, and we have stabilized vaccines that are very difficult to stabilize. Now, we would like to apply this to the COVID vaccine and we're quite hopeful that that will work as well.”
Today’s donors support tomorrow’s impacts
Although the pandemic may have slowed some research at the University of Alberta, funding from the COVID-19 and Emerging Pathogens Fund has provided a source of stability and allowed Vehring to continue his work, he said.
“Grants like the COVID-19 and Emerging Pathogens Fund serve a very important function—they are like the starter you put on barbecue coal to get them going,” he said. “Without that support, sometimes these kinds of projects don't get off the ground.”
Vehring said he also appreciates the willingness of donors to support long-term projects like his that will benefit future generations.
“Basic research often takes many decades to get to fruition—for example, this vaccine I'm working on currently may not go into humans for five years or more,” he said. “However, in 2050, when antibiotic resistance has become a really massive problem, we will be glad that we invested in it in 2020!”
The COVID-19 and Emerging Pathogens Fund was supported primarily through public donations. A month-long University of Alberta fundraising campaign in May 2020 for COVID-19 research, using the global movement Giving Tuesday NOW as a launch pad, received more than $200,000 from donors—including foundation partners and a few matching gifts. The funds were then directed through the Li Ka Shing Institute of Virology towards six new COVID-19 related projects across three faculties, including Vehring’s project in Engineering.