The booster dose of the Covid-19 vaccine from AstraZeneca significantly increases the levels of antibodies against the Omicron variant of the SARS-CoV-2 (B.1.1.529), according to data from a new laboratory study carried out by the Oxford University (UK) and published on the bioRxiv prepress server, so it has not yet been reviewed by other scientists.
The levels observed after the third booster dose were higher than the neutralizing antibodies found in individuals who had previously been infected and had recovered naturally from Covid-19 (Alpha, Beta, Delta and original strain variants).
Sera obtained from vaccinates one month after receiving the third booster dose neutralized the omicron variant to levels broadly similar to those observed one month after the second dose against the Delta variant.
The study analyzed blood samples taken from infected with Covid-19; of those who had been vaccinated with a two-dose schedule and a third booster dose; and of those who had reported a previous infection with other variants of Covid-19. The study included samples from 41 people who had received three doses of the AstraZeneca vaccine.
“It is very encouraging to see that current vaccines have the potential to protect against omicron after a third booster dose. These results support the use of third booster doses as part of national vaccination strategies, especially to limit the spread of variants of concern. , including the omicron “, has commented Professor John Bell, Professor of Medicine at the Oxford University (UK) and one of the study investigators.
For his part, the executive vice president of R&D for biopharmaceutical products of AstraZeneca, Mene Pangalos, has highlighted that these “make trust that the vaccine should be administered as a third booster dose.” “It is also important to look beyond antibodies to better understand how vaccines offer protection against omicron. As we better understand omicron, we believe that we will find that the T-cell response provides long-lasting protection against severe disease and hospitalizations.” , has added about it.
Data from another laboratory study support the effect of this omicron vaccine, as those vaccinated with two doses retained neutralizing activity against omicron, although a decrease was observed compared to the original strain. In other studies, it has been shown to elicit a diverse and long-lasting T-cell response to multiple variants, leading to a broader response than antibodies alone, potentially contributing to protection against Covid-19 .
AstraZeneca is collecting real-world scientific evidence evaluating efficacy against the omicron variant with academic groups in the southern African region. The company is also testing blood samples from participants in the company’s phase II / III trial for neutralizing activity when given as a third booster dose against omicron, for both ‘Vaxzevria’ and its next-generation vaccine. against COVID-19 under investigation, AZD2816. Data from these studies are expected “shortly”.