With respiratory illnesses ravaging children around the US, vaccine partners Pfizer and BioNTech announced Monday that they are seeking regulatory authorization to offer their bivalent COVID-19 vaccine to children ages 6 months to 4 years—but not as a booster; instead it would be part of an updated primary series.
Currently, the bivalent vaccine, which targets the coronavirus omicron subvariants BA.4 and BA.5 in addition to an ancestral strain, is only available as a booster dose to Americans ages 5 years and up. Although BA.5 is no longer dominant in the US, its sublineages now reign. The Centers for Disease Control and Prevention recently published real-world effectiveness data indicating that the bivalent boosters increased protection against symptomatic COVID-19 infection over protection provided by the previous boosters.
For now, children under 5 only have had access to a primary series—two small doses of Moderna’s original vaccine or three small doses of Pfizer/BioNTech’s original vaccine. Both were first authorized on June 17 after a rollercoaster regulatory process that lasted months.
Now, Pfizer is asking the Food and Drug Administration to authorize an amended primary series to include the bivalent vaccine. The updates series would be two doses of the original vaccine followed by a third dose with the bivalent vaccine.
“With the high level of respiratory illnesses currently circulating among children under 5 years of age, updated COVID-19 vaccines may help prevent severe illness and hospitalization,” the two companies said in a joint press release.
If authorized, the new primary series wouldn’t help boost protection in young children already vaccinated with a primary series and still under the age of 5. But few children in this age group have received a primary series—and it’s unclear if an updated primary series would move more parents to get their children vaccinated.
According to the latest data from the CDC, only 2 percent of infants ages 6 months to 2 years and 4 percent of toddlers ages 2 to 4 have completed a primary series.