Since the start of the pandemic, our scientists have been involved in the global response to COVID-19. We’ve conducted pre-clinical trials of two COVID-19 vaccine candidates as part of an international effort to develop a vaccine.
And we're collaborating again – leading a pre-clinical trial to evaluate Mynvax’s new ‘heat-stable’ vaccine candidate.
Vaccines often need cold storage
Most of the approved COVID-19 vaccines, now in use around the world, require some form of refrigeration.
The Oxford-AstraZeneca vaccine must be kept between 2 to 8°C. The Pfizer-BioNTech, another vaccine approved in Australia, requires specialised cold storage at minus 70°C.
Transporting these products relies on a supply chain of freezers and temperature-controlled shipping methods called the “cold chain.”
However, there are places in Australia, the Indo-Pacific and throughout the world, where it’s not possible to keep vaccines at low temperatures. There may also be regular interruption to electricity supply or delivery due to seasonal weather. And many remote or resource-constrained places simply may not have ultralow temperature freezers available.
Warm-temperature stable vaccine
Fortunately, scientists around the world are working on developing heat-tolerant vaccines.
Researchers at the Indian Institute of Science (IISc) and biotech start-up Mynvax have been developing a new ‘warm’ vaccine candidate that does not require refrigeration.
Results have shown that Mynvax formulations triggered a strong immune response in mice to SARS-CoV-2, the virus that causes COVID-19. The vaccine remains stable at 37°C for up to a month and at 100°C for up to 90 minutes.
Testing Mynvax antibodies
Our COVID-19 project leader, Dr S.S. Vasan, co-authored the peer-reviewed journal article recently published in ACS Infectious Diseases.
He led a study to assess blood samples – or sera – from vaccinated mice for efficacy against all key coronavirus variants. This includes the Delta variant currently spreading globally and in parts of Australia.
The team conducted the study at our Australian Centre for Disease Preparedness (ACDP), our secure biocontainment laboratory in Geelong.
“The mice received different formulations of Mynvax’s vaccine candidate, to test which one might provide the best antibody response,” Vasan said.
“My team exposed the blood samples, containing antibodies, to several strains of live coronavirus. Our tests included the Alpha, Beta, Gamma and Delta SARS-CoV-2 variants.
“Our data show that all formulations of Mynvax tested resulted in antibodies capable of consistent and effective neutralisation for all the coronavirus variants we tested,” he said.
Phase 1 clinical trials
Results of our study will assist in the decision of which Mynvax formulation to use in Phase 1 clinical trials in people.
Authorities in India are planning to run Phase 1 clinical trials using the most suitable candidate later this year.
The peer-reviewed paper, Immunogenicity and protective efficacy of a highly thermotolerant, trimeric SARS-CoV-2 receptor binding domain derivative, was published by ACS Infectious Diseases on 15 July 2021.