“Pfizer Inc. and BioNTech SE announced today that the U.S. Food and Drug Administration (FDA) granted emergency use authorization (EUA) to provide a single booster dose of the companies’ Omicron BA.4/BA.5-adapted bivalent COVID-19 vaccine in children 6 months through 4 years of age (also referred to as under 5 years of age) at least 2 months after completion of primary vaccination with three doses of the Pfizer-BioNTech COVID-19 Original Vaccine,” according to the company’s release.
“Emergency uses of Pfizer-BioNTech COVID-19 Vaccine and Pfizer-BioNTech COVID-19 Vaccine, Bivalent have not been approved or licensed by FDA but have been authorized by FDA under an Emergency Use Authorization (EUA) to prevent Coronavirus Disease 2019 (COVID-19) in individuals aged 6 months and older. The emergency uses are only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of the medical product under Section 564(b)(1) of the FD&C Act unless the declaration is terminated or authorization revoked sooner,” the company said.
Under the expanded EUA, the bivalent booster dose may be given to children at least 2 months after they received a third dose of Pfizer’s monovalent vaccine. The FDA said children who have not yet completed their primary series should complete it with a dose of bivalent vaccine and are not eligible for a bivalent booster.
“[This] authorization provides parents and caregivers of children aged 6 months through 4 years of age who received the three-dose primary series with the monovalent Pfizer-BioNTech COVID-19 vaccine an opportunity to update their children’s protection by receiving a booster dose with the Pfizer-BioNTech COVID-19 bivalent vaccine,” Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, said in a press release.
In the release, the FDA said immune response data from a study of 60 children aged 6 months to 4 years showed that participants had an immune response to both strains 1 months after receiving the bivalent shot.
It also detailed findings from a clinical study that included 24 participants aged 6 months through 23 months and 36 participants aged 2 years through 4 years of age. Common side effects in the former group included irritability, drowsiness, injection site redness, pain and swelling, decreased appetite, fatigue and fever; and the most common side effects in the latter group included fatigue, injection site pain, redness and swelling, diarrhea, vomiting, headache, joint pain and chills.
Recall, the reformulated bivalent COVID boosters were not tested on humans – only mice.
So the bivalent boosters tested in these human studies were not exactly the same as the bivalent ones being administered now in clinics, pharmacies, and other vaccination sites throughout the country. No, if you want human clinical trial data specifically on the bivalent BA.4/5 booster, you’re gonna have to wait a little while. According to a company announcement on August 31, the human clinical trial for the Moderna bivalent BA.4/5 booster is “fully enrolled and currently underway.” That same day, Gretchen Vogel reported for Science that the clinical trial for the Pfizer-BioNTech bivalent BA.4/5 booster will commence in September this month.
So what data specific to the BA.4/BA.5 boosters, did the FDA use to expand the EUAs to include the BA.4/BA.5 boosters? Well, the answer is at least in part very “mice.” Apparently, both Moderna and Pfizer-BioNTech have provided non-human animal data on the BA.4/BA.5 boosters to the FDA to state their case for the EUA. But they haven’t yet shown this data to the rest of the scientific community or the public.