Pfizer-BioNTech Seeks FDA Approval of COVID-19 Vaccine for Children Under 5

Today, Pfizer and its partner BioNTech asked the US Food and Drug Administration (FDA) to approve its 2-dose COVID-19 vaccine regimen for children younger than 5 years of age.

According to a report by The New York Times, Pfizer-BioNTech is pushing for FDA approval despite some trial evidence suggesting 2 doses of its vaccine did not evoke the desired autoimmune response. Only children 6 months-2 years old demonstrated an adequate immune response after 2 doses of Pfizer-BioNTech’s COVID-19 vaccine; vaccine trial doses for young children were 3 mg, or 1/10 the strength of the adult doses.

Pfizer-BioNTech received approval on December 17, 2021 from the FDA and European Medicines Agency to add a third dose to its clinical vaccine trial of children 6 months to 4 years old. At the time they announced the dosage change, Pfizer-BioNTech said, “These updates were informed by the effectiveness data for three doses of the vaccine for people 16 years and older, and the early laboratory data observed with Delta and other variants of concern, including Omicron, which suggest that people vaccinated with three doses of a COVID- 19 vaccine may have a higher degree of protection.”

However, its EUA request is still only to administer 2, 3 mg doses of the vaccine to children under 5.

The FDA noted the concerning rise in hospitalizations of young children with severe COVID-19 disease, as the highly infectious Omicron variant continues to spread rapidly.

"Having a safe and effective vaccine available for children in this age group is a priority for the agency and we're committed to a timely review of the data, which the agency asked Pfizer to submit in light of the recent Omicron surge. Furthermore, children are not small adults. Because they're still growing and developing, it's critical that these vaccines are evaluated in well-designed and well-conducted clinical trials," acting FDA commissioner Janet Woodcock, MD, said in a statement.

Currently the only COVID-19 vaccine approved for children and adolescents under 18 years, Pfizer-BioNTech’s vaccine has been shown to wane in efficacy after a few months. For this reason, and due to Omicron’s unprecedented ability to cause breakthrough infections, the FDA and US Centers for Disease Control and Prevention (CDC) updated their booster vaccine recommendations.

Now, all persons 12 and older are strongly recommended to receive an additional mRNA booster vaccine:

• 6 months after initial vaccination for Moderna (mRNA-1273) recipients
• 5 months after initial vaccination for Pfizer-BioNTech (BNT162b)
• 2 months after initial vaccination for Janssen (Johnson & Johnson; Ad26.COV2.S) recipients
• Both mRNA vaccines are currently preferred over the Janssen vaccine, as boosters and as a primary series, though vaccination with Janssen is recommended if no other COVID-19 vaccine is available.