LOS ANGELES (CNS) - USC researchers said today they have developed a polio vaccine that doesn't require refrigeration.
The injectable vaccine, which was freeze-dried into a powder, kept at room temperature for four weeks and then rehydrated, offered full protection against the polio virus when tested in mice, according to the research team whose study appears in the Nov. 27 issue of the journal mBio.
“Stabilization is not rocket science, so most academics don't pay much attention to this field,” said the study's first author, Woo-Jin Shin, a fellow in the lab of Jae Jung, chair of the Department of Molecular Microbiology and Immunology at the Keck School of Medicine of USC. “However, no matter how wonderful a drug or vaccine is, if it isn't stable enough to be transported, it doesn't do anyone much good.”
Polio, a highly infectious disease which causes lifelong paralysis and disability mostly in young children, is on the brink of complete eradication, with 22 reported cases worldwide in 2017. No cases have originated in the United States since 1979, but there are still countries where vaccination rates are spotty, putting young children are at risk.
The biggest hitch to complete eradication has been creating a temperature-stable vaccine for use in developing countries where refrigeration may be unavailable, according to the researchers, who noted that recent polio cases have been reported in Nigeria, Papua New Guinea, Syria and Pakistan.
By removing moisture through freeze-drying, researchers have created temperature-stable vaccines for measles, typhoid and meningococcal disease. But scientists haven't been able to make a polio vaccine that retains potency through freeze-drying and rehydration.
According to a USC statement, Shin and his colleagues “used two lab techniques -- liquid chromatography and high-throughput screening -- that allowed them to analyze a high volume of ingredients and formulations until they found one that worked. Jung's hope is that a foundation or company will take over the project to pay for human studies and bring the injectable vaccine onto the market.”
In addition to Shin, the study's authors are Daiki Hara and Jae Jung of the Keck School of Medicine, and Francisca Gbormittah, Hana Chang and Byeong S. Chang of Integrity Bio Inc., a company that specializes in biologics, or medicines made from substances found in living things.