Pfizer and BioNTech have begun the trial of Omicron-specific Covid vaccine in adults aged up to 55, the companies said in a statement Tuesday. They are likely to file for regulatory approval of the shot by March, Pfizer's CEO Albert Bourla had announced earlier.
The volunteers are split into three groups. The first involves people who previously received two doses of the current Pfizer-BioNTech vaccine 90-180 days prior to enrollment, and will receive one or two doses of the Omicron vaccine.
The second will be people who got three doses of the current vaccine 90-180 days prior to the study and will receive either another dose of the original shot or an Omicron-specific vaccine. The third and final group are people who have never previously received a Covid vaccine, and will receive three doses of the Omicron-specific vaccine.
“While current data showed that boosters against the original Covid strain continued to protect against severe outcomes with Omicron, the company was acting out of caution," Pfizer's head of vaccine research Kathrin Jansen said, quoted in a company statement.
"We recognize the need to be prepared in the event this protection wanes over time and to potentially help address Omicron and new variants in the future," she said.
Ugur Sahin, CEO of the German biotech company BioNTech added that the protection of the original vaccine against mild and moderate Covid appeared to wane more rapidly against Omicron.
"This study is part of our science-based approach to develop a variant-based vaccine that achieves a similar level of protection against Omicron as it did with earlier variants but longer duration of protection."
