Three doses of Pfizer-BioNTech are being used to combat the Omicron threat. According to the study, the COVID-19 vaccine neutralises the new variant

A preliminary laboratory study found that three doses of the Pfizer-BioNTech COVID-19 vaccine neutralize the Omicron variant (B.1.1.529 lineage), while two doses have significantly lower neutralization titers.

After three doses, serum antibody induced by the Pfizer-BioNTech COVID-19 vaccine (BNT162b2) neutralizes the SARS-CoV-2 Omicron variant, according to preliminary laboratory findings from Pfizer Inc and BioNTech SE.

The third dose of BNT162b2 increased neutralizing antibody titers by 25-fold compared to the first two doses against the Omicron variant; titers after the booster dose are comparable to titers observed after two doses against the wild-type virus, which are associated with high levels of protection, according to a press release from Pfizer and BioNTech on the Omicron variant.

Sera obtained one month after receiving the booster vaccination (third dose of BNT162b2 vaccine) neutralized the Omicron variant to levels comparable to those observed after two doses of the wild-type SARS-CoV-2 spike protein.

Sera from people who received two doses of the current COVID-19 vaccine showed a more than a 25-fold reduction in neutralization titers against the Omicron variant compared to wild-type, indicating that two doses of BNT162b2 may not be enough to protect against infection with the Omicron variant.

However, because the vast majority of epitopes targeted by vaccine-induced T cells are unaffected by Omicron mutations, the companies believe that vaccinated individuals may still be protected against severe forms of the disease and are closely monitoring global real-world effectiveness against Omicron.

A third dose may provide more robust protection, according to the release, as data from additional studies show that a booster with the current COVID-19 vaccine from Pfizer and BioNTech increases antibody titers by 25-fold.

According to preliminary data from the companies, a third dose provides a similar level of neutralizing antibodies to Omicron as two doses against wild-type and other variants that emerged before Omicron.

These antibody levels are linked to high efficacy against the wild-type virus as well as these variants. A third dose also significantly boosts CD8+ T cell levels against multiple spike protein epitopes, which are thought to correlate with disease protection. The vast majority of these epitopes remain unchanged in the Omicron spike variant compared to the wild-type virus.

Because the mutations in the Omicron variant do not affect 80% of the epitopes in the spike protein recognized by CD8+ T cells, two doses may still induce protection against severe disease.

According to the release, the companies are continuing to advance the development of a variant-specific vaccine for Omicron and expect to have it available by March if an adaptation is required to further increase the level and duration of protection – with no change expected to the companies’ four billion dose capacity for 2022.

“While two doses of the vaccine may still provide protection against severe disease caused by the Omicron strain, preliminary data show that protection is improved with the third dose of our vaccine,” said Albert Bourla, Chairman and CEO of Pfizer.

“The best course of action to prevent the spread of COVID-19 is to ensure that as many people as possible are fully vaccinated with the first two-dose series and a booster,” Bourla added.

“Our preliminary, first dataset suggests that a third dose may still provide adequate protection from the disease of any severity caused by the Omicron variant,” said Ugur Sahin, MD, CEO and Co-Founder of BioNTech.

“Broad vaccination and booster campaigns around the world could help us protect people all over the world and get through the winter season. We are still working on an adapted vaccine that we believe will help to induce a high level of protection against Omicron-induced COVID-19 disease as well as longer protection than the current vaccine “Sahin added.

“The best way to prevent the spread of COVID-19 is to get as many people as possible fully vaccinated with the first two-dose series and a booster,” Bourla added.

“Our preliminary, first dataset suggests that a third dose may still provide adequate protection from disease of any severity caused by the Omicron variant,” said Ugur Sahin, MD, BioNTech’s CEO and Co-Founder.

“Global vaccination and booster campaigns could help us protect people all over the world and get through the winter season. We are still developing an adapted vaccine that we believe will induce a high level of protection against Omicron-induced COVID-19 disease as well as longer protection than the current vaccine “Sahin elaborated.