The Candy-Like Vaccine

Rotavirus is a dangerous pathogen for children, elders and persons with a weak immune system.

It induces severe diarrhea and vomiting in children, killing roughly 600-650,000 annually, aged 0-2 years, mainly in developing nations.

Rotavirus vaccine is currently delivered in a liquid or freeze-dried form that must be refrigerated for transport and storage, resulting very expensive where it's most needed.

Moreover, newborns sometimes spit out the liquid, but this is less likely to occur with the new vaccine developed at John Hopkins: a strip that sticks to and dissolves on the tongue in less than a minute, like a popular breath-freshener.

7 students developed the thin film which is wrapped in a material that protects it in the child's stomach. In the small intestine, viruses are released and they induce an immune response to impede a rotavirus infection. The thin film is easy to store and transport and does not require refrigeration and the Johns Hopkins Technology Transfer staff has already applied for a provisional patent. "Because the strips are in a solid form, they would cost much less to store and transport than the liquid vaccine. We wanted this to be as simple and as inexpensive as possible", said lead researcher Hai-Quan Mao.

The development of the virus faced some obstacles: the manufacturing process used to make breath strips as the employed harsh solvent and high temperatures would kill the virus. There was also the issue of a protective coating against the stomach acid but solvable in the neutral environment of the small intestine. The students managed to refine a room-temperature production and drying process making the strips of FDA approved biocompatible polymer coating.

The coating is pH sensitive, releasing its virus load only when the environment has the right acidity. "What the students have accomplished is a way to incorporate a pH-responsive polymer system that works with an oral quick-dissolving thin film. It's still very early in the process, but the pieces they've come up with have been very encouraging.

We have the delivery vehicle prototype. I'm optimistic that we can make this work with our vaccine. Animal testing could begin later this year," said Vu Troung, cofounder and chief scientific officer at Aridis Pharmaceuticals, a San Jose, Calif., the company that funded the research. "This is probably the second-most important childhood vaccine needed in the developing world, right behind a malaria vaccine," said senior author Christopher Yu.