A possible vaccine for coronavirus being developed in the UK is ready to enter the next phases of clinical trials, researchers have said.
Scientists at Oxford University, which is one dozens of places around the world in the race to find a vaccine, said on Friday it would be recruiting 10,260 adults and children for the next stage.
The first phase of clinical trials began in April and involved more than 1,000 healthy adults.
This second phase will now be expanding the age range of participants in order to see whether the vaccine reacts differently for different age groups.
Among another large grouping of healthy adults, the trial will also be assessing a small number of children aged between 5-12 years; a grouping between 56-69 years, and more in the over 70s bracket.
A third phase will be more generally looking at whether vaccine protects people from catching the virus, by studying a large group of people over the age of 18.
Professor Andrew Pollard, head of the Oxford Vaccine Group, said the studies had progressed "very well" and that the new phases would help to gain a better idea of whether the vaccine could help protect the wider population.
He added: "We are very grateful to the huge support of the trial volunteers in helping test whether this new vaccine could protect humans against the pandemic coronavirus."
Meanwhile, Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said he was "so proud" to be collaborating with Oxford University of the trial, and said praised the "ground-breaking scientific research" for entering late-stage trials so fast.
He added: "We will do everything in our power to engage with governments, multilateral organisations and partners around the world to increase production and distribution and ensure rapid, fair and equitable distribution of a globally accessible vaccine."