The Food and Drug Administration authorised the Moderna and Pfizer coronavirus vaccines for the nation’s youngest children Friday, a relief to parents who have waited 18 months to protect their babies, toddlers and preschoolers since shots first became available.
Regulators followed the recommendation of independent experts on an advisory panel, who voted unanimously Wednesday in favour of both vaccines. All Americans other than the roughly 20 million children younger than 5 have had the option of protecting themselves against Covid-19 for months and are eligible for booster shots.
Moderna’s two-dose vaccine is for children 6 months through 5 years old, while Pfizer’s three-dose vaccine is for children 6 months through 4 years old.
A separate advisory panel to the Centers for Disease Control and Prevention began two days of meetings on the matter Friday. The FDA’s action permits vaccines to be used, but doctors look to the CDC’s advisory committee for specifics on how to use them, and acceptance of the vaccines will depend partly on the strength of the agency’s recommendations. After the panel votes Saturday, the CDC’s director, Rochelle P. Walensky, will issue her own recommendation, the final step before distribution.
The Biden administration began shipping the vaccines Friday.
Pfizer’s and Moderna’s studies showed that the omicron variant of the virus greatly dulled the power of the vaccines to prevent symptomatic infection in young children, just as it did for adults.
Pfizer has said that two doses of its vaccine were about 28 per cent effective in preventing disease, while three doses were 80 per cent effective. But that 80 per cent estimate was based on only 10 cases in a subset of 1,678 trial participants.
Moderna’s vaccine was about 51 per cent effective in children 6 months to 2 years old and 37 per cent effective in children 2 through 5.
Both vaccines provoked an immune response comparable to that triggered in young adults, the primary measurement the agency used to measure effectiveness. Asked to compare them at a press briefing, Peter Marks, who heads the FDA’s vaccine division, said that Moderna’s vaccine might trigger an immune response “slightly more rapidly,” while Pfizer’s might “bring a greater response after the third dose.”
He said parents should feel comfortable with either, and recommended they go with whichever one is available.