A coronavirus vaccine changed to beat a new variant has been injected into people for the first time as the University of Oxford begin its latest trial.
Academics who created the original Oxford Astra Zeneca jab have updated their blueprint to target the South African variant, which is less susceptible to the vaccines than other strains.
The mutation became the prime candidate for the first “variant vaccine” and the booster jab, called AZD2816, ins now being given to 2,250 volunteers from the UK, Poland, Brazil and South Africa.
Volunteers are only eligible for the trial if they have already received two doses of an approved Covid vaccine more than three months before the study began.
Sir Mene Pangalos, executive vice president of BioPharmaceuticals R&D at AstraZeneca, said: "It is important we continue to stay ahead of genetically distinct variants of the coronavirus.
“AZD2816 should help broaden individuals' immune response against emerging variants of concern.”
Professor Sir Andrew Pollard, chief investigator and director of the Oxford Vaccine Group, said: "Testing booster doses of existing vaccines and new variant vaccines is important to ensure we are best prepared to stay ahead of the pandemic coronavirus, should their use be needed."
His team announced today that at third shot of the Oxford-AstraZeneca vaccine produces a strong immune response, but they also said there was not yet evidence such jabs were needed, especially given shortages in some countries.
The Oxford University study found that a third dose of the vaccine increases antibody and T-cell immune responses, while the second dose can be delayed up to 45 weeks and also lead to an enhanced immune response.
The British government has said it is looking at plans for an autumn vaccine booster campaign, with three-fifths of adults already having received both doses of a COVID vaccine.
Sir Andrew added: "We do have to be in a position where we could boost if it turned out that was necessary... [but] we don't have any evidence that that is required.
"At this point with a high level of protection in the UK population and no evidence of that being lost, to give third doses now in the UK whilst other countries have zero doses is not acceptable."
