Protection against Omicron coronavirus variant improves with three vaccine doses, Pfizer says

(CNN) Preliminary lab studies show two doses of the Pfizer/BioNTech vaccine may not provide sufficient protection against the Omicron coronavirus variant, but three doses are able to neutralize it, the companies said in a news release on Wednesday.

source https://www.cnn.com/2021/12/08/health/pfizer-omicron-vaccine-data/index.html