A ‘warm’ COVID-19 vaccine being developed by scientists from India and Australia, suitable for remote regions lacking access to the cold storage needed to transport current vaccines, appears to be effective against new strains of the virus currently pushing Australian states back into lockdown.
The CSIRO has been evaluating the heat-tolerant COVID-19 vaccine formulations developed by the Indian Institute of Science and biotech startup Mynvax for its effectiveness against all variants of the coronavirus.
While current vaccines require refrigeration to remain effective – 2-8°C for AstraZeneca, minus 70°C for Pfizer – the new vaccine remained stable at 37°C for up to a month and at 100°C for up to 90 minutes, according to a paper published in the peer-reviewed ACS Infectious Diseases journal.
CSIRO scientists at the Australian Centre for Disease Preparedness in Geelong contributed to the study by assessing vaccinated mice sera (blood samples) for efficacy against key coronavirus variants, including the Delta strain that’s put Sydney in lockdown for at least five weeks and forced Melbourne to also reintroduce lockdown restrictions from tonight.
CSIRO’s COVID-19 project leader Dr S.S. Vasan, who co-authored the paper, said the vaccinated mice showed a strong response to all variants of coronavirus.
“Our data shows that all formulations of Mynvax tested result in antibodies capable of consistent and effective neutralisation of the Alpha, Beta, Gamma and Delta SARS-CoV-2 variants of concern,” he said.
CSIRO’s evaluation of the different Mynvax formulations will support selection of the most suitable candidate for planned human clinical trials in India later this year.
CSIRO’s health and biosecurity director, Dr Rob Grenfell, said: “A thermostable or ‘warm vaccine’ is critical for remote or resource-limited locations with extremely hot climates which lack reliable cold storage supply chains, including regional communities in Australia’s outback and the Indo-Pacific region.”
The paper, Immunogenicity and protective efficacy of a highly thermotolerant, trimeric SARS-CoV-2 receptor binding domain derivatives is available here.
The CSIRO study was funded by a grant from Australia’s Federal Department of Finance.