Booster dose vaccine protects against Covid Omicron variant, says Pfizer

Pfizer and BioNTech today announced results from an initial laboratory study demonstrating that serum antibodies induced by the Pfizer-BioNTech Covid-19 vaccine neutralise the SARS-CoV-2 Omicron variant after three doses.

Sera collected one month after receiving the booster immunisation (third dosage) neutralised the Omicron variant to levels equivalent to those seen after two doses of the wild-type SARS-CoV-2 spike protein.

According to the companies’ preliminary data, a third dose provides a similar level of neutralising antibodies to Omicron as is observed after two doses against wild-type and other variants that emerged before Omicron. These antibody levels are associated with high efficacy against both the wild-type virus and these variants. A third dose also strongly increases CD8+ T cell levels against multiple spike protein epitopes, which are considered to correlate with the protection against severe disease. Compared to the wild-type virus, most of these epitopes remain unchanged in the Omicron spike variant.

“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 the third dose of our vaccine,” said Albert Bourla, chairman and chief executive officer, Pfizer.

“Our preliminary, first dataset indicates that a third dose could still offer a sufficient level of protection from the disease of any severity caused by the Omicron variant,” said Ugur Sahin, M.D., CEO and co-founder of BioNTech.

While these results are preliminary, the companies said they will continue to collect more laboratory data and evaluate real-world effectiveness to assess and confirm protection against Omicron.

On November 25, the companies started to develop an Omicron-specific Covid-19 vaccine. The development will continue as planned in the event that a vaccine adaption is needed to increase the level and duration of protection against Omicron.

First batches of the Omicron-based vaccine can be produced and are planned to be ready for deliveries within 100 days, pending regulatory approval.

The companies have previously announced that they expect to produce four billion doses of BNT162b2 in 2022, and this capacity is not expected to change if an adapted vaccine is required.