Professor Sarah Gilbert, the lead researcher of the vaccine development programme at the University of Oxford, said trials were currently being held up by a lack of vaccine (see above).
The vaccine needs to be created from a line of immortal cells which are infected with a harmless adenovirus fused with coronavirus to act as a “Trojan horse”, but it takes time for the cells to proliferate and then be purified and concentrated into a vaccine.
“We’re being limited by our ability to supply vaccine into those trials and we’re trying to manufacture more,” said Prof Gilbert. “We have vaccines in around 10,000 people, but we need to keep making more and that is preventing us going any faster at the moment.
“We use a particular immortal cell line from the 1970s and they are having to manufacture at large scale, which is a problem they’re addressing at a great speed. It’s a technical challenge.”
But she said that she had not been in any doubt that the vaccine would trigger an immune response, adding: “We never really had major concerns about how it was going to turn out.”
Speaking about the race to develop the jab, she said: “We’ve certainly had some very long days, but we’ve got a large team of people working on this. The pandemic has affected the way everyone is living now, and actually, for us, we have carried on doing what we do everyday, and kept coming to work. But we couldn’t have done much else even if we had wanted.”