Dr Rob Grenfell, CSIRO’s Health and Biosecurity Director
Developing a safe and effective vaccine is a highly complex process. The world has rallied around creating a COVID-19 vaccine, with more than 170 vaccine candidates at varying stages of development around the globe.
Late-stage or large-scale human trials for the Oxford-AstraZeneca vaccine are being undertaken across multiple countries, involving tens of thousands of people. The purpose of these trials are to examine the safety and efficacy of the vaccine candidate.
We understand that the trials have been voluntarily paused to independently review an unexplained illness in one of the trial participants. We understand this is a single event and at this stage the cause of the illness is unknown.
Events like this are not uncommon in clinical trials, and are a standard part of the scientific process.