One day soon, it may be possible to deliver vaccines without vials, needles, or cold storage.
Researchers at McMaster University and Rapid Dose Therapeutics are partnering to develop a quick dissolving strip for oral delivery of viral proteins.
Current mRNA vaccines — like those developed by Pfizer/BioNTech and Moderna to protect against COVID-19 — need to be stored in freezers because mRNA isn’t stable at warmer temperatures. The mRNA encodes instructions for the body to make the Spike protein on the coronavirus that causes COVID-19.
Proteins themselves, on the other hand, can be kept stable at temperatures up to 40 °C. Added to a thin film, they could readily be distributed globally in a package as simple as an envelope.
The technology is still in pre-clinical trials, but tiny strips loaded with a model protein have been shown to trigger antibody production in animals. The team is about to use actual Spike protein in the next phase of their study, with the initial supply of protein provided by the National Research Council of Canada.
Unlike a pill, the vaccine strips don’t need to be swallowed. Instead, a vaccine recipient holds the strip under their tongue or next to their cheek until it dissolves to release the viral protein. This allows the protein to avoid the harsh environment of the stomach and be absorbed directly into the oral mucosa that line the inside of the mouth. Lots of immune cells live there, making it an ideal location to deliver proteins for vaccination.
The strips are easy for anyone to use at any age, which would make it possible to vaccinate citizens without recruiting large teams of highly trained staff to give injections. They could be readily distributed to remote locations and help convince people with a fear of needles to step up and get vaccinated, improving access and vaccine uptake. The dry strip format would also eliminate the need for specialized vials, syringes, and needles that are currently in high demand and straining global supply chains.
There is still a lot of work needed to prove that this technology would be safe and effective, but it’s a promising idea that addresses many of the struggles that come with injection-based vaccines.
Innovation will provide lasting benefits for immunization campaigns well into the future. Vaccines save lives, and making them easier to distribute and administer could help us get them to every corner of the planet.
