The trial involves approximately 2,250 fully vaccinated participants, either with original AstraZeneca or an mRNA shot, across UK, South Africa, Brazil and Poland.
The World Health Organization considers the Beta variant, also known as the South African variant, to be one of concern.
“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,” Prof. Sir Andrew J Pollard, chief investigator and director of the Oxford Vaccine Group, said in a press release.
The modified vaccine, labeled AZD2816, will be administered as a booster shot at least three months after the patients' previous jab, or as a two-dose vaccine to those who are unvaccinated.
"It is important we continue to stay ahead of genetically distinct variants of the coronavirus," according to Sir Mene Pangalos, executive vice president of BioPharmaceuticals R&D.
"AZD2816 should help broaden individuals' immune response against emerging variants of concern," he said. "Initiating the Phase II/III trial for AZD2816 means we can be prepared should a variant vaccine be required in the future."