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# Pfizer/BioNTech Begin Omicron Vaccine Study
- URL: https://www.fdaweb.com/pfizer-biontech-begin-omicron-vaccine-study/
- Published: 2022-01-25T12:00:00.000Z
- Updated: 2026-09-14T17:29:51.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5151002

Pfizer and BioNTech have begun a clinical study to evaluate the safety, tolerability and immunogenicity of an Omicron-based vaccine candidate in healthy adults aged 18 through 55 years. The 1,400-patient study, which will have three cohorts examining different regimens of their current Covid-19 vaccine or an Omicron-based vaccine, will determine the potential need for variant-based vaccines, [according to the companies](https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-initiate-study-evaluate-omicron-based?ref=fdaweb.com).

The companies say that [clinical](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fwww.pfizer.com%2Fnews%2Fpress-release%2Fpress-release-detail%2Fpfizer-and-biontech-publish-data-two-laboratory-studies&esheet=52568093&newsitemid=20220124005896&lan=en-US&anchor=Clinical&index=4&md5=8aedb6a6a56f89efa03987dbe4ff4ae7&ref=fdaweb.com) and [real-world](https://cts.businesswire.com/ct/CT?id=smartlink&url=https%3A%2F%2Fpapers.ssrn.com%2Fsol3%2Fpapers.cfm%3Fabstract%5Fid%3D4011905&esheet=52568093&newsitemid=20220124005896&lan=en-US&anchor=real-world&index=5&md5=be750e988bf40fe363b8e2ebf21da7b8&ref=fdaweb.com) data continue to find people who are vaccinated, particularly those that have received a booster, maintain strong protection against Omicron, particularly against severe disease and hospitalization. Previously, they have announced plans to produce four billion doses of their Covid-19 Vaccine this year, and this is not expected to change if an adapted vaccine is required.