AstraZeneca, a British-Swedish multinational pharmaceutical and biotech company based in the United Kingdom, said on Thursday that when given as a third dose, Vaxzevria — previously known as Covid-19 Vaccine AstraZeneca — boosted the immune response to the SARS-CoV-2 variants of Beta, Delta, Alpha and Gamma.
A separate analysis of samples from the trial also showed an increased antibody response to the Omicron variant, it said in a press release.
The results were observed among individuals previously vaccinated with either Vaxzevria or an mRNA vaccine.
A separate Phase IV trial reported in The Lancet showed that a booster shot of Vaxzevria substantially increased antibody levels following first shots of CoronaVac made by China’s Sinovac Biotech.
Given the urgent global need for protection against Omicron, AstraZeneca is submitting this additional data to health authorities across the world as evidence supporting Vaxzevria as a third dose, irrespective of the primary vaccines.
Mene Pangalos, AstraZeneca’s executive vice president for biopharmaceuticals research and development, said this data shows that the Vaxzevria vaccine has an important role to play as a booster.
“Vaxzevria has protected hundreds of millions of people from Covid-19 around the world. Given the ongoing urgency of the pandemic and the vaccine’s increased immune response to the Omicron variant, we will continue to progress regulatory submissions around the world for its use as a third dose,” he said.
These studies show that a third dose of Vaxzevria after two initial doses of the same vaccine, or after mRNA or inactivated vaccines, strongly boosts immunity against Covid-19, said Prof Andrew J Pollard, chief investigator and director of the Oxford Vaccine Group at the University of Oxford.
“The Oxford-AstraZeneca vaccine is suitable as an option to enhance immunity in the population for countries considering booster programmes, adding to the protection already demonstrated with the first two doses,” he said.