On May 17, 2022, Pfizer and BioNTech announced the U.S. Food and Drug Administration expanded emergency use authorization to include a booster dose after completion of the primary series of the Pfizer-BioNTech COVID-19 Vaccine in children 5 through 11 years of age. The booster dose is given at least five months after the second dose of the two-dose primary series and is the same 10-ﾵg dose of the Pfizer-BioNTech COVID-19 Vaccine. To date, more than 8 million 5- to 11-year-olds in the U.S. have completed a primary series.

The expanded EUA is based on data from the Phase 2/3 clinical trial, which showed that a booster dose of the Pfizer-BioNTech COVID-19 Vaccine elicited a strong immune response in this age group, generating neutralizing antibodies against both the Omicron variant and wild-type SARS-CoV-2 virus regardless of prior SARS-CoV-2 infection. No new safety signals were observed. The third dose was well tolerated, with a safety profile similar to the two-dose primary series.

This Phase 2/3 data builds on efficacy data for the primary two-dose series which showed 90.7% efficacy in children 5 through 11 without prior SARS-CoV-2 infection, measured from 7 days after the second dose, at a period when Delta was the prevalent strain.

The companies have already submitted an application to the European Medicines Agency for a booster dose in this age group and are planning to file with other regulatory agencies around the world. The Pfizer-BioNTech COVID-19 Vaccine is the only COVID-19 vaccine authorized for use in the U.S. for children 5 through 11 years of age.

The Phase 1/2/3 clinical trial evaluating the safety, tolerability, and immunogenicity of a 3-µg formulation of the Pfizer-BioNTech COVID-19 Vaccine on a three-dose schedule in children ages 6 months through 4 years (also known as under 5) is ongoing. Initial data is expected in the coming weeks.

The Pfizer-BioNTech COVID-19 Vaccine, which is based on BioNTech’s proprietary mRNA technology, was developed by both BioNTech and Pfizer. BioNTech is the Marketing Authorization Holder in the United States, the European Union, the United Kingdom, Canada and the holder of emergency use authorizations or equivalents in the United States (jointly with Pfizer) and other countries. Submissions to pursue regulatory approvals in those countries where emergency use authorizations or equivalent were initially granted are planned.

The Phase 1/2/3 trial initially enrolled up to 4,500 children ages 6 months to under 12 years of age in the United States, Finland, Poland, and Spain from more than 90 clinical trial sites. Additional children have been enrolled in all age groups following study amendments and the trial currently includes more than 10,000 children. The trial was originally designed to evaluate the safety, tolerability, and immunogenicity of the Pfizer-BioNTech COVID-19 Vaccine on a two-dose schedule (approximately 21 days apart) in three age groups: ages 5 to under 12 years; ages 2 to under 5 years; and ages 6 months to under 2 years. Based on the Phase 1 dose-escalation portion of the trial, children ages 5 to under 12 years received a two-dose schedule of 10 µg each while children under age 5 received a lower 3-µg dose for each injection in the Phase 2/3 study. The trial enrolled children with or without prior evidence of SARS-CoV-2 infection. In December 2021, Pfizer and BioNTech announced the companies would test a third 3-µg dose given at least two months after the second dose in children under age 5 and a third dose of the 10-µg formulation in children 5 to under 12 years of age.