Video report by ITV News Political Correspondent Romilly Weeks
The Oxford/AstraZeneca vaccine offers only limited protection against mild disease caused by the South African variant of coronavirus, according to research.
But the British company said early data from the study, due to be published on Monday, has shown the jab can protect against severe disease caused by the mutation.
The study, first reported by the Financial Times, into the E484K mutation involved some 2,000 people, most of whom were young and healthy.
The research is only preliminary for now and needs to be reviewed.
A spokesperson for AstraZeneca, said: “In this small Phase I/II trial, early data has shown limited efficacy against mild disease primarily due to the B.1.351 South African variant. However, we have not been able to properly ascertain its effect against severe disease and hospitalisation given that subjects were predominantly young, healthy adults.
“We do believe our vaccine will still protect against severe disease, as neutralising antibody activity is equivalent to other Covid-19 vaccines that have demonstrated activity against more severe disease, particularly when the dosing interval is optimised to eight-12 weeks.
“Further, correlates of protection are unknown and other immune responses, such as T cell responses may have a role in protection against disease and initial data indicates these responses may remain intact in B.1.351 variants.
“Oxford University and AstraZeneca have started adapting the vaccine against this variant and will advance rapidly through clinical development so that it is ready for Q4 delivery should it be needed.”
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Oxford vaccine lead researcher Professor Sarah Gilbert said that the current vaccines “have a reduction in efficacy against some of the variant viruses.”
She added: “What that is looking like is that we may not be reducing the total number of cases but there’s still protection in that case against deaths, hospitalisations and severe disease.”
She told the BBC’s Andrew Marr Show: “Maybe we won’t be reducing the number of cases as much, but we still won’t be seeing the deaths, hospitalisations and severe disease. “That’s really important for healthcare systems, even if we are having mild and asymptomatic infections to prevent people going into hospital with Covid would have a major effect.”
She added researchers working on a new vaccine designed to combat the South African variant of coronavirus are hopeful it will be ready to administer by the autumn.
Professor Gilbert said her team currently has “a version with the South African spike sequence in the works”. She went on: “It’s not quite ready to vaccinate people with yet, but as all of the developers are using platform technologies, these are ways of making a vaccine that are very quick to adapt. “This year we expect to show that the new version of the vaccine will generate antibodies that recognise the new variant. Then it will be very much like working on flu vaccines. “It looks very much like it will be available for the autumn. “We’re already working on the first part of the manufacturing process in Oxford, that will be passed on to other members of the manufacturing supply chain as we go through the spring. "
But Professor Robin Shattock, who is leading Covid-19 vaccine research at Imperial College London, urged caution about the study’s early findings.
He told BBC Breakfast: “It’s a very small study with just over 2,000 people and it’s not published so we can only judge it from the press release and press coverage. But it is concerning to some extent that we’re seeing that it’s not effective against mild or moderate disease.”
Meanwhile Vaccines Minister Nadhim Zahawi told ITV News that annual vaccines could be required to combat Covid-19 variants.
He told ITV News: "I suspect we're going to be in a world where we have an annual vaccination programme, for Covid in the way we have an annual vaccination programme for flu and we may need a booster in the winter for this current vaccination programme."
Mr Zahawi said Prime Minister Boris Johnson's message is not only to vaccinate now but think of the future "on how we future-proof our vaccination programme" from Covid.
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It comes after research released on Friday indicated that the Oxford/AstraZeneca jab is effective at fighting the new UK coronavirus variant.
Andrew Pollard, professor of paediatric infection and immunity, and chief investigator on the Oxford vaccine trial, said: “Data from our trials of the ChAdOx1 vaccine in the United Kingdom indicate that the vaccine not only protects against the original pandemic virus, but also protects against the novel variant, B117, which caused the surge in disease from the end of 2020 across the UK.”
Also on Friday, public health officials said the outcomes of targeted tests to track the South African variant in England could take up to two weeks.
Door-to-door testing as part of urgent efforts to swab 80,000 people came after 11 cases of the variant were identified in the previous few days in people who had no links to travel – suggesting it may be spreading in communities.
And people in more postcode areas in England are being "strongly encouraged" to get tested in a bid to stop the spread of new coronavirus variants.
The targeted areas have been extended to include people living in Worcestershire WR3 postcode, the PR9 postcode in Sefton, Merseyside, and within areas in Bristol and South Gloucestershire.