The companies said a third dose appears to provide a similar number of antibodies as a two-dose series against the original virus and other variants. People who have two shots of the vaccine may still be protected against severe cases, they added.
The companies on Nov. 25 began developing an Omicron-specific vaccine and said Wednesday that the work will continue 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.
South African researchers this week reported that studies suggest the Omicron variant can partiallly 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.
David Lim contributed to this report.