800 Victorians sought for COVID-19 booster shot trial

The Coalition for Epidemic Preparedness Innovations (CEPI) and the Murdoch Children’s Research Institute (MCRI) are seeking 800 Victorians for a global trial investigating whether vaccinating people with a lower COVID-19 booster dose is just as effective as a full dose, but with fewer side effects.

The study would also secure additional data on administering ‘mix-and-match’ COVID-19 vaccine schedules. Participants aged 18 years and older in Victoria, who have not yet received a COVID-19 vaccine booster, are being recruited. They would receive either the Pfizer or Moderna vaccine and be followed for up to 12 months.

The trial lead, Murdoch Children’s Professor Kim Mulholland, said the findings were expected to provide important data on the advantages of vaccinating people with a lower booster dose of a COVID-19 vaccine, which could guide future vaccination strategies.

“All countries are struggling with the issue of how best to maintain COVID-19 immunity in their populations,” he said. This trial will specifically examine how best to vaccinate communities with follow-up booster shots and the timings around these subsequent booster doses. While reduced doses could provide the opportunity for large financial savings for countries, they are also likely to produce fewer side effects, improving their uptake.

“The results could also potentially advise whether boosting with a vaccine that is different to the one used in the first two doses may lead to superior immune responses and protection.”

Up to 3800 healthy participants are being invited to take part in the trial across Australia, Indonesia and Mongolia.

The launch of the trial follows a recent statement made by the World Health Organization urging broader global access to COVID-19 vaccines for both primary vaccinations and booster doses to maintain COVID-19 immunity in light of the emergence and impact of new variants like Omicron.

Administering reduced vaccine shots has previously been used to maximise global vaccine supply during outbreaks of yellow fever and polio. The Murdoch Children’s also recently published supportive research for this dose-sparing strategy for the experimental rotavirus vaccine RV3-BB.

CEPI will provide up to $12.3 million in funding to the global trial led by the Murdoch Children’s in collaboration with Padjadjaran University and the University of Indonesia in Indonesia, and the Government of Mongolia, and with support from the global non-profit organisation PATH. The study is said to be the first under CEPI’s program of work looking at reduced COVID-19 booster shots. In line with CEPI’s access policy, access to the trial data will be shared through open-access publications and via scientific meetings to ensure all can benefit from the research findings.

Participants in Victoria would be required to visit The Royal Children’s Hospital for four blood tests, complete an online diary card for seven days post vaccination and receive three follow-up calls.

For more on the trial visit www.mcri.edu.au/research/projects/cepi-covid-19-booster-study or email COVID.Booster@mcri.edu.au.

Image credit: ©stock.adobe.com/au/ThamKC