Pfizer, BioNTech begin omicron-specific COVID-19 vaccine study

COVID-19 vaccine-makers Pfizer and BioNTech announced Tuesday that they would test an omicron-specific vaccine candidate in healthy adults ages 18 to 55. 

The companies said there would be three trials examining different regimens of the current Pfizer-BioNTech vaccine for an omicron-based vaccine.

The study will also draw upon some participants from the companies’ Phase 3 COVID-19 booster study, evaluating up to 1,420 people. 

The first cohort received two doses of the Pfizer-BioNTech vaccine 90-180 days before enrollment and will receive one or two doses of the omicron-based vaccine. 

In the second, participants received three doses of the Pfizer-BioNTech vaccine during the same timeframe and will receive one dose of the same vaccine or the omicron-based vaccine. 

Lastly, the third trial participants will get three doses of the omicron-based vaccine.