Pfizer and BioNTech announced results from a Phase 2/3 trial showing a favorable safety profile and robust neutralizing antibody responses in children 5 to 11 years of age using a two-dose regimen of 10 µg administered 21 days apart, which is a smaller dose than the 30-µg dose used for people 12 and older.
The antibody responses in the participants given 10-µg doses were comparable to those recorded in a previous Pfizer-BioNTech study in people 16 to 25 years of age immunized with 30-µg doses, the companies said, adding that these are the first results from a pivotal trial of a COVID-19 vaccine in this age group.
Pfizer and BioNTech said they plan to share these data with the U.S. Food and Drug Administration (FDA), European Medicines Agency (EMA) and other regulators. For the United States, the companies expect to include the data in a near-term submission for emergency use authorization (EUA) as they continue to accumulate the safety and efficacy data required to file for full FDA approval in this age group. Top line readouts for the other two age cohorts from the trial — children 2-5 years of age and children 6 months to 2 years of age – are expected as soon as the fourth quarter of this year, the companies said.
The data summarized from this Phase 2/3 study, which is enrolling children 6 months to 11 years of age, was for 2,268 participants who were 5 to 11 years of age and received a 10-µg dose level in a two-dose regimen.
The Phase 1/2/3 trial initially enrolled up to 4,500 children ages 6 months to 11 years of age in the United States, Finland, Poland, and Spain from more than 90 clinical trial sites. It was designed to evaluate the safety, tolerability, and immunogenicity of the Pfizer-BioNTech vaccine on a two-dose schedule (approximately 21 days apart) in three age groups: ages 5 to 11 years; ages 2 to 5 years; and ages 6 months to 2 years. Based on the Phase 1 dose-escalation portion of the trial, children ages 5 to 11 years received 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.
