Pfizer to test third dose of COVID-19 vaccine in children

Pfizer Inc and its German partner BioNTech SE said on Friday they would include and evaluate a third dose of their COVID-19 vaccine in an ongoing trial in children six months to under five years of age.

The decision was made after an analysis showed the two-dose vaccine generated an immune response in the two to under five-year-old population, which was inferior to what was previously observed in 16 to 25 year olds.

The study will now include a third dose of 3 microgram given at least two months after the second dose of the two-dose series to provide high levels of protection, the companies said.

If the three-dose study is successful, Pfizer and BioNTech expect to submit data to regulators to support an Emergency Use Authorization for children six months to under five years of age in the first half of 2022.

The vaccine received full approval for ages 16 and above in the United States in August. The shot also has an emergency use authorization for five to 15 year olds.

On Thursday, the companies filed for full approval of their COVID-19 vaccine with the U.S. Food and Drug Administration to include adolescents aged 12 to 15.