In a highly successful collaboration with Sementis Limited and QIMR Berghofer Medical Research Institute, researchers at the University of South Australia have developed new technology set to deliver vaccines for many diseases and conditions, more cheaply and efficiently.
The new approach has taken the world’s first and most successful vaccine against smallpox – genetically altered it to improve its safety and efficacy – and created a new vaccine platform able to deliver multiple antigens to guard against serious infectious diseases, including the mosquito-borne zika and chikungunya viruses.
The new, altered vaccine, named the Sementis Copenhagen Vector (SCV), has been tested in preclinical proof of concept studies and been shown to provide protection against Chikungunya infection and its virus-induced complications and Zika virus – importantly preventing transmission of the virus to the foetus during pregnancy as well as a persistent infection of the testis.
The results of the research have been published today in the prestigious journal Nature Communications and leader of the UniSA research team, Professor John Hayball said the outcome is the result of a highly effective collaboration with Sementis and QIMR Berghofer over several years.
“We have now proved this is a very effective delivery vehicle for a vaccine protecting against multiple infectious diseases,” Professor Hayball said.
“Working together, we will continue to explore the potential of this platform to deliver multiple disease vaccines.
“This work puts us well on the way to delivering health benefits to millions of people around the world by providing more effective and accessible vaccines.
“The potential applications of this Australian research for a range of diseases and other conditions is enormous.”
Professor Andreas Suhrbier, QIMR Berghofer Inflammation Biology group leader, said preclinical proof-of-concept studies showed that Sementis’ new vaccine afforded protection against chikungunya infection and prevented persistent virus-induced arthritic complications.
“In addition, these studies have shown that it can afford protection against Zika virus infection and, very importantly, prevent the transmission of the virus during pregnancy to the foetus and persistent infection of the testis,” he said.
Advance Queensland research fellow Dr Natalie Prow, who received a grant from the Queensland Government to test the vaccine at QIMR Berghofer, said it was her hope that human clinical trials would be the next step.
“The SCV vaccine would be a welcomed medical countermeasure in countries where both chikungunya and Zika virus coinfection exist,” she said.
In the next phase of this work, Sementis has been invited to use the preclinical services of the renowned US Government National Institute of Health’s Institute of Allergy and Infectious Diseases (NIAID) laboratories to evaluate the SCV vaccines in a non-human primate vaccination study.
The study will be funded by NIAID and bring the vaccine one step closer.
Sementis’ Chairman, Maurice O’Shannassy, says the production of a viral vectored vaccine in a CHO cell substrate is a game-changer in terms of the improved economics of vaccine production and providing vaccines on a global scale.
“Previous vaccinia-based vaccine vector systems have used chicken embryo fibroblasts for manufacture, which is associated with a number of manufacturing and safety issues,” he said.
“Being able to manufacture a vectored vaccine using CHO cells is a world first and offers a number of advantages in the event of an outbreak, including rapid manufacture scale-up and cold chain (refrigeration) independent distribution capacity.”
Zika virus is a new and emerging virus that is transmitted by mosquitos where infection often causes no or mild symptoms similar to a very mild form of dengue fever. But in some adults, Zika virus can lead to Guillain Barre syndrome, a condition in which the immune system attacks the nerves.
Perhaps the most devastating manifestation of Zika virus infection is the array of congenital abnormalities in the foetuses and infants of women infected while pregnant.
Zika virus infection can persist in the male reproductive tract, where infected males can transmit the virus to sexual partners during this period of persistent infection, which dramatically increases the risk that an infected male inadvertently transmits the virus to a pregnant partner. Currently, there are no antiviral drugs or vaccines for Zika virus.
Chikungunya is a viral infection caused by the chikungunya virus, also transmitted by mosquito, the very same mosquitos that transmit Zika virus.
In some cases, Chikungunya is asymptomatic – persons do not exhibit symptoms, but those with symptoms usually suffer from sudden fever and severe muscle and joint pain and in a few cases chronic joint pain may last for several weeks or months and may be accompanied by eye, gastrointestinal, neurological, and heart complications. Chikungunya is rarely fatal and treatment includes supportive care of symptoms as there are no antiviral treatments or vaccines available.