Pfizer Vaccine for Children 5 to 11 is Safe with Robust Antibody Response

A Phase 2/3 trial conducted by Pfizer and BioNTech revealed that the Covid-19 vaccine was safe and generated a “robust antibody response” in children ages 5 to 11.

These are the first such results released for this age group for a US Covid-19 vaccine. Pfizer said it plans to submit to the U.S. Food and Drug Administration for emergency use authorization soon.

The company said it hopes to have approval by the end of the calendar year. “Over the past nine months, hundreds of millions of people ages 12 and older from around the world have received our COVID-19 vaccine,” said Albert Bourla, Chairman and Chief Executive Officer, Pfizer.

“We are eager to extend the protection afforded by the vaccine to this younger population, subject to regulatory authorization, especially as we track the spread of the Delta variant and the substantial threat it poses to children,” Bourla continued.

“Since July, pediatric cases of COVID-19 have risen by about 240 percent in the U.S. – underscoring the public health need for vaccination. These trial results provide a strong foundation for seeking authorization of our vaccine for children 5 to 11 years old.

"And we plan to submit them to the FDA and other regulators with urgency.”

The clinical trial

The trial included 2,268 participants ages 5 to 11 and used a two-dose regimen of the vaccine administered 21 days apart. The trial used a 10-microgram dose – smaller than the 30-microgram dose that has been used for those 12 and older.

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 “We are pleased to be able to submit data to regulatory authorities for this group of school-aged children before the start of the winter season,” said Dr. Ugur Sahin, CEO and co-founder of BioNTech.

“The safety profile and immunogenicity data in children aged 5 to 11 years vaccinated at a lower dose are consistent with those we have observed with our vaccine in other older populations at a higher dose.”