Australian researchers are a step closer to developing a vaccine for the painful and debilitating mosquito-borne chikungunya virus, with a potential candidate showing promising results in laboratory tests.
The vaccine was invented and developed by the Australian biotech company Sementis and uses an altered form of the vaccinia virus to protect against chikungunya and smallpox.
Scientists from QIMR Berghofer Medical Research Institute and the Sansom Institute for Health Research at the University of South Australia have been testing the efficacy and safety of the new Sementis Copenhagen Vector (SCV) vaccine.
The findings have been published in the journal Molecular Therapy.
Chikungunya virus, which occurs throughout Africa, Asia and the Americas, causes chronic and acute arthritis, fever and rash.
It is closely related to Ross River virus but is more serious because it occasionally causes death and severe forms of illness requiring hospitalisation, mainly in the elderly and very young.
The disease is spread by the mosquito Aedes aegypti, which is endemic in North Queensland, and by the Asian Tiger Mosquito, Aedes albopictus, which has spread globally to reach islands in the Torres Strait.
QIMR Berghofer’s Professor Andreas Suhrbier said the SCV vaccine offered a number of advantages.
“The technology behind this vaccine means that in the event of an outbreak, production can be quickly ramped up. Also, it doesn’t need refrigeration, meaning it would be far more practical to distribute in developing countries,” Professor Suhrbier said.
“In our laboratory tests, the vaccine induced strong immunity to chikungunya and small pox, and prevented chikungunya virus, and a model virus for smallpox, from causing disease.
“Importantly, we found that the vaccine was safe in immune-deficient mice.
“Our society has greater numbers of people than ever before living with and managing pre-existing medical conditions, so it’s important the vaccine is safe for them.”
Sementis chief scientist Dr Paul Howley, who developed the vaccine, said the tests showed the vaccine technology was powerful with an excellent safety profile.
“The results are very exciting and set the stage for Sementis to continue exploring the capacity and capability of the vaccine platform,” Dr Howley said.
“Initially, we used chikungunya as a test case for this vaccine technology, but there are numerous diseases and conditions that could potentially be treated using this innovation.
“Sementis, QIMR Berghofer and the University of South Australia are already well-advanced in road testing the platform for a number of other conditions and the results so far are very promising.”
Head of the Experimental Therapeutics Laboratory at the University of South Australia, Professor John Hayball, said the next step was to prepare for human clinical trials.
“We are now one step closer to having a vaccine that could protect humans against the next epidemic of chikungunya virus disease,” he said.
“If the vaccine is successful in human clinical trials, it could prevent the suffering of millions of people across the globe.”
QIMR Berghofer scientist, Dr Natalie Prow, who received an Advance Queensland Fellowship from the Queensland Government to test the vaccine, said researchers are already working on applying the vaccine technology to the Zika virus, which causes neurological complications, including microcephaly, in newborns.