Last month, scientists at Oxford University began immunizing more than 1,000 volunteers with their vaccine candidate in a preliminary trial created to test the shot's safety.
Sarah Gilbert, professor of vaccinology at the Jenner Institute, said: "We have had a lot of interest already from people over the age of 55 years who were not eligible to take part in the phase I study, and we will now be able to include older age groups to continue the vaccine assessment".
Only a handful of the vaccines in development have advanced to human trials, an indicator of safety and efficacy, and the stage at which most fail.
ChAdOx1 nCoV-19 is made from a weakened version of a common cold virus from chimpanzees that has been genetically changed to make it impossible for it to grow in humans. However, the developers argued that the vaccine had successfully protected the animals from more severe infections. In Britain's soon-to-begin larger tests, researchers will address how Oxford's shot will affect older adults, who are at high risk from COVID-19.
"Having looked at the data myself, it is really quite promising in the sense that in the phase-one study, which is the first step toward the development of a vaccine through its multiple phases, the vaccine induced what we call neutralizing antibodies, as opposed to just binding antibodies", Fauci said.
"For these groups, researchers will be assessing the immune response to the vaccine in people of different ages, to find out if there is variation in how well the immune system responds in older people or children", the researchers said. Health Secretary Alex Azar described the deal as a "major milestone" in US President Donald Trump's program to fast-track a Covid-19 vaccine, dubbed Operation Warp Speed.
AstraZeneca could supply potential coronavirus vaccine from September
But Pollard acknowledged there were still many challenges ahead, including how long it will take to prove the vaccine works - particularly since transmission has dropped significantly in Britain - and any potential manufacturing complications.
AstraZeneca had already signed an agreement to supply 100 million doses of the vaccine to the British government and it reiterated it hopes to start delivery in September.
Adding: "There is uncertainty about how many cases there will be in the next three months".
A number of efforts to develop a coronavirus vaccine are underway around the world.
On NPR's "Morning Edition" Friday, he delivered a similar message. The disease has accounted for at least 333,489 deaths around the world, including at least 94,729 people in the U.S.
Turkey warns against attacks on its presence in Libya
The focus of the conflict has shifted towards Tarhouna, the biggest remaining LNA stronghold in northwest Libya. The LNA, however, said it had already withdrawn from those areas in a humanitarian gesture for Ramadan.
Is COVID-19 a bioweapon? Here's what the experts say
That work, also looking at the possible role of intermediate hosts, should include "scientific and collaborative field missions". Early on day one, member states unanimously chose to kick the can down the road on whether to grant Taiwan observer status.