Thin-Film Vaccine Platform Could Revolutionize Vaccine Distribution and Access

A team of investigators may have solved the problem of how to preserve vaccines on long journeys to remote and under-served areas of the world.

But they didn’t start out with that goal.

Maria A. Croyle, RPh, PhD, and colleagues this month published a new report in Science Advances showing that a thin film platform appears to preserve vaccines at room temperature for months at a time. The idea could solve one of the thorniest issues surrounding vaccination campaigns in hard-to-reach corners of the world. However, Croyle told Contagion® that she and her team were initially trying to tackle a separate problem.

“We started working on this technology as part of a large project to develop a needle-free vaccine against Ebola,” said Croyle, a professor of pharmaceutics at the University of Texas, Austin. “To be honest, we were more interested in making vaccines more acceptable to people where outbreaks were prevalent and resources were low.”

Toward that end, Croyle and colleagues began developing methods to stabilize the vaccine for oral and nasal delivery. The nasal platform was relatively straightforward, she said, but the oral platform was much more difficult.

“The idea for the film came to my group as we were discussing a documentary in which insect DNA was stabilized in amber,” she said. “We tasked ourselves to devise our own amber with natural, FDA approved ingredients and, after much screening, identified a formulation that encased live viruses within a peelable film matrix.”

That discovery solved the problem Croyle and colleagues were trying to solve. It allowed a vaccine to pass through the gastrointestinal system and successfully boost immune response in both rodents and primates.

That might have been the end of the story, except for a fluke observation.

“When the Ebola project was wrapping up, we found a series of films that were prepared almost 3 years prior and stored on the lab bench without refrigeration,” she said.

The team was sure that the virus in the film would be dead, but they checked anyway, and were shocked by what they found.

“[W]hen the films were rehydrated there were as many active viruses present as there were 3 years ago!” she recalled. “We then knew we were on to something.”

The discovery is a powerful one because one of the biggest challenges faced by organizations like the World Health Organization (WHO) and local public health services is finding ways to get vaccines to people in remote areas, given that most vaccines have very specific temperature requirements, generally requiring either refrigeration or freezing. That makes transport and storage a major problem in under-resourced parts of the world. The WHO estimates that temperature-related storage problems lead to the destruction of nearly half of freeze-dried and one-quarter of liquid vaccines each year.

Croyle said she and her colleagues are moving quickly to try and get the technology to the places that need it most. She and her team have been awarded 3 patents for technologies associated with the film platform, and they have formed a biotechnology company to license the technology. They hope to work with industrial and governmental partners in the near future, she said.

“We feel this is the most direct way to get this technology into the hands of the people that need it the most,” she said.