AstraZeneca didn't reveal any information about the possible side effect except to call it "a potentially unexplained illness".
Pfizer and Moderna are each close to fully enrolling the 30,000 participants in each of their trials, with some analysts predicting they will be finished within the next two weeks. We're testing the vaccine with our partners at three trial sites in Brazil and seven in South Africa, for example. It is in Phase 3 - meaning thousands of patients are receiving the vaccine - and it is generating strong immune responses without an significant safety concerns. "In this light, we would be able to update you regarding any development on this front by next weekend only", said Prof.
All worldwide trial sites have now been put on pause while an independent investigation reviews the safety data before regulators decide whether the trial can restart, the BBC's Medical Editor Fergus Walsh reports.
Mr Coatsworth said Australia like many other governments has invested in several coronavirus vaccine candidates, "knowing not all of them will get through".
It is thought the trials could resume in a matter of days.More news: Coronavirus: 307 new COVID-19 cases, 6 of them in Galway
There's a good chance we'll know whether the ChAdOx1 nCoV-19 vaccine is effective before the end of 2020.
"We believe this pledge will help ensure public confidence in the rigorous scientific and regulatory process by which COVID-19 vaccines are evaluated and may ultimately be approved", they added in a joint statement.
The pledge includes companies such as AstraZeneca in the United Kingdom, and Johnson & Johnson in the United States.
In it, the companies say "the safety and well-being of vaccinated individuals" would always be their top priority.
Pharmaceuticals giant AstraZeneca on Tuesday said that it had to "voluntarily paused" a randomized clinical trial of its coronavirus vaccine.More news: EasyJet trims flights on weak demand, quarantine rules
Despite this, China and Russian Federation have begun inoculating some key workers with domestically developed vaccines.
The industry's collective stance comes close on the heels of U.S. President Donald Trump pressuring the FDA into giving emergency use authorization to plasma therapy to treat COVID-19, the disease caused by SARS-CoV-2.More news: F1: BIC bids fond farewell to Williams team founders