When Irish scientist Prof Tess (Teresa) Lambe heard the interim results of the Oxford AstraZeneca Covid-19 vaccine trials at the weekend, she almost broke down with happiness and relief.
After 10 months working at the heart of an effort to make a vaccine against SARS-CoV-2, which causes Covid-19, she could not wait to hear the analysis of Phase 3 clinical trial results so far.
"When I was being brought through the results, I stopped the person who was talking and I asked: 'Do we have efficacy?' I couldn't wait to get the answer," says Lambe, an associate professor and investigator in the Jenner Institute of the University of Oxford. "I was told 'Yes, we do' and I practically broke down, it was great. I was delighted, absolutely delighted."
Those results were announced publicly on Monday morning by press release from the University of Oxford, where Lambe works, and by biopharmaceutical company AstraZeneca, which is a partner on the project. Full results in a scientific paper are due in coming weeks.
The interim analysis of trials in the UK and Brazil show the vaccine is highly effective in preventing Covid-19, and that no hospitalisations or severe cases of the disease were reported in participants receiving the vaccine.
One dosing regimen, where two full doses were given at least a month apart, resulted in 62 per cent efficacy. Another – a half dose to start, followed by a full dose at least a month later – resulted in 90 per cent efficacy.
Unlike the Pfizer-BioNTech and Moderna vaccines, whose interim results were announced in recent weeks, the Oxford-AstraZeneca vaccine will need only refrigeration – not freezers – for storage, making logistics easier. There is also indication that it could help reduce transmission of the virus, but this will require further investigation.
Years of research
Lambe and colleagues co-designed the new vaccine based on the structure of the emerging coronavirus at the start of 2020, and she has worked on bringing it through early trials with collaborators and on delivering some of the results for the large clinical trials. The Jenner Institute at Oxford is headed by Dublin-born vaccinologist Prof Adrian Hill.
The new vaccine builds on years of research, notes Lambe, who is originally from Kildare and studied science at University College Dublin.
“We have had this platform technology for many many years, and by the time the SARS-CoV-2 outbreak started we had already used it as a platform technology for other outbreak pathogens, so we knew what to do and how to do it,” she says.
“Honestly this has been such a team effort, I have had my team in there over weekends, and it is not just us, not just in Oxford, it is all our trial sites and the volunteers. Without them this would not have happened.”
Lambe stresses the need to get vaccines to people around the world. “We are committed with AstraZeneca and partners to make three billion doses by the end of next year, to make a real impact around the world, for it to be available at cost during the pandemic with no profit and to make it available to low-to-middle income countries.”
It may sound counterintuitive that an initial half dose could ultimately help to boost immunity more, but the smaller first dose might be priming the immune system in a way that results in a more effective response.
Lambe sees it as an interesting immunological question, and will work on research into the reasons for the success of the half-dose-then-full-dose regimen. The team will also continue to look at the trial data to assess how long immunity lasts, and whether this differs across age groups.
Peer review
Lambe and colleagues will submit the findings for publication by peer review in the next day or so. “I really wanted to celebrate when we got the results at the weekend, but I knew the next few days would be really busy, so I am looking forward to celebrating during the week,” she says.
When asked if the vaccine would be ready to roll out before the end of the year, she told the Today with Claire Byrne Show on RTÉ radio that was not for her to decide; it was up to the Government and regulatory bodies.
“I’ve had my head down trying to make a vaccine for the last year or so. Those types of policy decisions are not up to me, unfortunately.”
She added: “I’ve never worked as hard, or been as driven. I’m definitely looking forward to the end of the day, when I can have a glass of wine.”
Prof Louise Richardson, vice-chancellor at the University of Oxford, who is originally from Ireland, said at a briefing: "This is a great day for the University of Oxford and for universities everywhere. Pushing at the frontiers of knowledge with partners across the globe and putting our extraordinary brainpower in service to society is what we do best."
Immunologist Prof Luke O'Neill, who is based at Trinity College Dublin, says he is happy that the third Monday in a row has brought another positive announcement about a vaccine. "And this one has the ease of storage and suggests a block in transmission, too, which means it will be even better at slowing spread," he adds.
Dr Anne Moore, based at UCC school of biochemistry and cell biology, says the Oxford results are "really promising", and she is looking forward to learning more about the durability of all the emerging vaccines. "A key question that needs to be answered for all of these vaccines is to understand what is the minimum immune response that is needed to maintain protection. This will be a key factor in durability."
