Pfizer Board Member Says New Data Questions the Efficacy of the Vaccine Prompting FDA to Delay Decision to Vaccinate Kids Under 4

Pfizer said on Friday that it will wait for its data on a three-dose series of the vaccine, because it believes three doses "may provide a higher level of protection in this age group." Data on the third dose is expected in early April, the company said. 

Pfizer said in December that two doses didn’t generate a strong enough immune response in its trial of children ages 2 to 4. For young children, Pfizer’s vaccine has a dosage of 3 micrograms. For children ages 5 to 11, the dosage is higher, at 10 micrograms. Still, the company asked the FDA this month to authorize these first two doses, with a plan to submit additional data in the coming weeks on a third dose. The full vaccination series would be three doses. 

The FDA was expected to publish an analysis of the Pfizer data Friday, ahead of an advisory committee meeting next week. The FDA said Friday the meeting has been postponed. Two people familiar with the FDA’s plans said there had already been a lot of pushback on the agency from outside experts who had concerns that Pfizer’s data wasn’t sufficient. 

The experts felt, one of the people said, that their concerns were “falling on deaf ears” within the agency. Federal regulators had initially wanted to begin reviewing the data on two doses of the vaccine while Pfizer continued to gather data on a three-dose regimen. 

Regulators believed two doses would provide enough — though less than ideal — protection against the omicron variant of the coronavirus as pediatric cases surged.