Pfizer-BioNTech Vaccine Booster Offers Protection Against Omicron Early Study Shows
Preliminary laboratory studies have shown that three doses of the Pfizer-BioNTech COVID-19 Vaccine can neutralize the Omicron variant (B.1.1.529 lineage), the vaccine makers announced.
Three doses of the Pfizer-BioNTech COVID-19 Vaccine neutralize the Omicron variant (B.1.1.529 lineage)
According to the preliminary laboratory results, three doses of the Pfizer-BioNTech COVID-19 Vaccine BNT162b2 increased the neutralizing antibody titers to the Omicron variation (B.1.1.529 lineage) by 25-fold.
A third dosage significantly raises CD8+ T cell numbers against numerous spike protein epitopes, which are thought to be linked to disease protection. The great majority of these epitopes are unaltered in the Omicron spike variation compared to the wild-type virus.
In the study, serum samples collected one month following the booster immunization (third dose of BNT162b2 vaccine) neutralized the Omicron variant at levels equivalent to those seen after two doses of the wild-type SARS-CoV-2 spike protein.
Albert Bourla, Chairman and Chief Executive Officer, Pfizer tweeted:
Two doses had more than a 25-fold lower neutralization but may still induce protection against severe disease
Serum samples from people who got two doses of the current COVID-19 vaccine had more than a 25-fold lower neutralization titer against the Omicron variant versus the wild-type.
Two doses demonstrated much lower neutralization titers, as 80% of epitopes in the spike protein recognized by CD8+ T cells are not affected by the mutations in the Omicron variant but may still induce protection against severe disease. The companies believe that vaccinated individuals with two doses may still be protected against the progression to severe forms of the disease because the mutations in Omicron do not affect the vast majority of epitopes targeted by vaccine-induced T cells. They are closely monitoring real global effectiveness against Omicron around the world.
Pfizer’s CEO Albert Bourla stated the companies press release:
“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine. Ensuring as many people as possible are fully vaccinated with the first two dose series and a booster remains the best course of action to prevent the spread of COVID-19.”
Ugur Sahin, M.D., CEO and Co-Founder of BioNTech also commented:
“Our preliminary, first dataset indicates that a third dose could still offer a sufficient level of protection from disease of any severity caused by the Omicron variant. Broad vaccination and booster campaigns around the world could help us to better protect people everywhere and to get through the winter season. We continue to work on an adapted vaccine which, we believe, will help to induce a high level of protection against Omicron-induced COVID-19 disease as well as a prolonged protection compared to the current vaccine.”
While these findings are preliminary, the companies will continue to gather additional laboratory data and examine the real efficacy globally in order to verify and validate Omicron protection and determine the best course of action.
Pfizer and BioNTech also began developing an Omicron-specific COVID-19 vaccine on November 25. If a vaccine adaptation is required to boost the amount and duration of protection against Omicron, the development will proceed as anticipated. Depending on regulatory approval, the first batches of the Omicron-based vaccine can be developed and delivered within 100 days, the companies confirmed in a press statement.
Other variant-specific vaccines tested by Pfizer and BioNTech showed extremely significant neutralizing titers with an acceptable safety profile. Based on their previous expertise, the businesses are confident that they will be able to offer an Omicron-based vaccine in March 2022 if necessary.
The companies have also started clinical trials with variant-specific vaccines (Alpha, Beta, Delta, and Alpha/Delta Mix), and the results will be submitted to regulatory agencies around the world to help speed up the process of adapting the vaccine and gaining regulatory authorization or approval for an Omicron-specific vaccine, if necessary. The companies previously said that they anticipate producing four billion doses of BNT162b2 by 2022, and this capacity is unlikely to alter if an adapted vaccine is needed.
About the Pfizer-BioNTech Laboratory Studies
Pfizer and BioNTech immediately evaluated a panel of human immune serum derived from the blood of persons who received two or three 30-g doses of the existing Pfizer-BioNTech COVID-19 vaccine using a pseudovirus neutralization test (pVNT) to determine the efficacy of BNT162b2 against the Omicron variant. Participants’ serum samples were collected three weeks after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine or one month after receiving the third dose.
The neutralizing antibody titer of each serum was measured against both the wild-type SARS-Cov-2 spike protein and the Omicron spike variant at the same time. The neutralizing antibody titers against the Omicron strain reportedly rose 25-fold after the third dosage. After three doses of the Pfizer-BioNTech COVID-19 vaccination, neutralization against the Omicron variant was equivalent to the neutralization level against the wild-type strain monitored in serum tests from people who got two doses of the companies’ COVID-19 vaccine: In the samples, the geometric mean titer (GMT) of neutralizing antibody against the Omicron variation was 154 (after three doses), compared to 398 (after three doses) against the Delta variant and 155 for the original strain (after two doses).
After a booster dosage of BNT162b2 against the Omicron variety, data on the durability of neutralizing titers over time will be obtained. The neutralizing antibody titers against the Omicron strain spike were 25-fold higher after the third dosage. After three doses of the Pfizer-BioNTech COVID-19 vaccination, neutralization against the Omicron variant was equivalent to that shown in serum samples from those who got two doses of the firms’ COVID-19 vaccine: Both BioNTech and Pfizer worked together to create the Pfizer-BioNTech COVID-19 vaccine, which is based on BioNTech’s unique mRNA technology. BioNTech is the holder of marketing authorizations or equivalents in the United States, the European Union, the United Kingdom, Canada, and other countries, as well as emergency use authorizations or equivalents in the United States (jointly with Pfizer). Submissions will be made to seek regulatory clearance in countries where emergency use authorizations or equivalents were first obtained.