COVID-19 vaccine Oxford/AstraZeneca trials booster jab to counter Beta variant

London, Jun 29: The University of Oxford in partnership with AstraZeneca said on Monday that it has begun vaccinations for a new phase in human trials to test a COVID-19 vaccine to combat the Beta variant, first identified in South Africa.

The AZD2816 booster shot will be administered to volunteers against the B.1.351 variant of concern (VOC), commonly known as the Beta variant. The Phase II/III trial, sponsored and led by AstraZeneca, will recruit approximately 2,250 participants across the UK, South Africa, Brazil and Poland.

For the booster study, participants must have received two doses of an approved COVID-19 vaccine three to 12 weeks apart more than three months prior to the study.

"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," said Professor Sir Andrew J. Pollard, chief investigator and director of the Oxford Vaccine Group at the University of Oxford.

AZD2816 will be administered to individuals who have previously been fully vaccinated with two doses of the original Oxford-AstraZeneca vaccine or an mRNA vaccine such as Pfizer/BioNtech, at least three months after their last injection. In non-vaccinated individuals, AZD2816 will be given as two doses, four or 12 weeks apart, or given as a second dose following a first dose of the original Oxford/AstraZeneca vaccine four weeks apart.

"The UK vaccine roll out 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," said Dr Maheshi Ramasamy, Principal Investigator at the Oxford Vaccine Group.

The new vaccine, known as AZD2816, has been designed using the same adenoviral vector platform developed by researchers at the University of Oxford using the ChAdOx platform technology, with minor genetic alterations to the spike protein based on the Beta variant.

Sir Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, 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. Initiating the Phase II/III trial for AZD2816 means we can be prepared should a variant vaccine be required in the future."

The study aims to assess the immune response to the Beta VOC with the new vaccine - for use potentially in combination with the current Oxford-AstraZeneca vaccine - as well as to better understand the disease and associated health problems. Initial data from the trial is expected later this year and, once available, will be submitted to regulators for assessment as a next-generation booster vaccine and through an expedited regulatory pathway.