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Covid booster: variant vaccine tested on people for the first time

Covid booster jabs


A variant vaccine developed to protect against the South African or Beta variant of Covid-19 has been injected into people for the first time.

The Astra Zeneca/ Oxford vaccine has been updated with minor genetic alterations to target the B.1.351 variant of concern, commonly known as the Beta variant. Human trials began yesterday to determine the immune response to this variant and the effectiveness of the booster vaccination.

The Beta variant was the first to be discovered in the UK and is still present in the UK at low levels. The variant vaccine contains ten minor changes across the spike protein but in all other ways is the same as the original Astra Zeneca vaccine.

The vaccine trials, which are a partnership between the University of Oxford and Astra Zeneca, will recruit around 2,250 volunteers from across the UK, South Africa, Brazil and Polland.

Within the UK participants must have received two doses of an approved Covid-19 vaccine three to 12 weeks apart at least three months prior to the study. Non-vaccinated individuals in the other study regions will receive two doses of the variant vaccine or will be given a second dose following a first dose of the original Oxford-AstraZeneca vaccine.

Dr Maheshi Ramasamy, principal investigator at the Oxford Vaccine Group, said: ‘The UK vaccine rollout programme has been incredibly successful at preventing hospitalisations and deaths, but we don’t know how long protection lasts. This study will provide vital evidence on whether further doses including “tweaks” against new virus variants may be needed in the future.’

Initial data from the trial is expected later this year. Professor Sir Andrew J Pollard, chief investigator and director of the Oxford Vaccine Group at the University of Oxford, added: ‘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.’

The researchers hope that the new variant vaccine will broaden individuals immune response as variants emerge and become a next-generation booster vaccine against Covid-19.