The U.S. Food and Drug Administration (FDA) has granted emergency authorization to the updated Pfizer-BioNTech COVID-19 vaccine as a booster for children as young as 6 months old, even though Pfizer has produced no clinical efficacy data for any age group.
FDA officials on March 14 said the emergency clearance was based on trial data that showed 60 children had “an immune response” after receiving the updated bivalent booster, and trial data that found 60 young children experienced side effects such as fatigue, diarrhea, and vomiting after bivalent vaccination.
None of the trial data has been released to the public.
The authorization means children aged 6 months to 5 years will be encouraged to get a booster dose just two months after the final dose of a three-dose Pfizer primary series.
The bivalent vaccines protected well against symptomatic infection for children aged 5 and older initially, but the protection waned to close to 50 percent after several months, according to federal data. There were no estimates for protection against severe illness.