Pfizer Says that a Vaccine Booster Dose is Effective Against the Omicron Variant

Pfizer has confirmed that a third dose of its vaccine appears to provide added protection against the new Omicron variant.

Two doses of Pfizer-BioNTech’s coronavirus vaccine may not offer enough protection against the Omicron variant but a booster shot increased antibody defenses 25-fold, according to preliminary laboratory results.

“It’s clear from these preliminary data that protection is improved with the third dose of our vaccine,” Pfizer Chairman and CEO Albert Bourla said in a statement. “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.”

The company’s early data has not been peer-reviewed.

While two doses of the vaccine provide some protection, a third dose appears to provide a similar number of antibodies against the Omicron variant as a two-dose series against the original virus and other variants.  However, people who have had two shots may still be protected against severe cases, they added.

“It is still not a complete escape variant — it is a partial escape variant,” said BioNTech CEO Uğur Şahin.

Still, he later added, “It is very clear our vaccine for the Omicron variant should be a three-dose vaccine. We believe this is the right way to go,” he said.

On Nov. 25, Pfizer and BioNTech announced they are developing an Omicron-specific vaccine. The companies said Wednesday they will continue their work in case the shot 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, Pfizer and BioNTech said.

The companies said they “have high confidence” they can deliver an Omicron-based vaccine in March 2022, if needed, and that it won’t affect plans to produce 4 billion doses of vaccines next year.

Şahin advised the public against waiting for a Omicron-specific vaccine before getting a third dose, which has shown strong antibody reaction in early vaccination studies.

“The data that we have clearly indicates the value of a third dose, and we should be really clear about that — that an Omicron vaccine, even if we start supply in March, will not be broadly available,” he said.

South African researchers this week reported that studies suggest the Omicron variant can partially evade protection from two Pfizer-BioNTech shots — but that people who were previously infected and had received two doses were able to largely neutralize the variant.