The local families stuck in COVID-19 limbo with unprotected children under age 5 received some relief this week.
Pfizer and its vaccine partner BioNTech applied Tuesday (Feb. 1) to expand U.S. Food and Drug Administration emergency-use authorization for their COVID-19 vaccine to include the formulation dosed for children 6 months to 4 years old. Children age 5 and over already have access to a higher-dose version of the vaccine.
The application requests FDA authorization for the first two 3-microgram shots of what is likely to become a three-dose primary series for these youngest children. The FDA had encouraged the application from the drugmakers now, even though Pfizer is still collecting data between now and March on how that third dose, administered at least eight weeks after the second, raises antibody levels.
The initial, two-dose series studied earlier this year was well tolerated and had successful safety data in clinical trials but did not, on its own, produce a high enough antibody response in 2- to 4-year-olds to achieve the desired level of protection. Children under age 2 did demonstrate an immune response similar to that seen in older children and young adults. Instead of starting over and testing a higher-dose, two-shot regimen, the drugmakers began exploring whether a third dose would provide the needed protection. Many routine childhood immunizations also follow a three- (or four-) dose series.
Applying for approval of the first two vaccines now would allow families to start the clock on full immunity and begin the series, meaning they would be eligible for a final shot almost immediately after future authorization of the third dose.
The FDA’s vaccine advisory committee could approve Pfizer’s application of the first two shots at its Feb. 15 meeting.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in a press release Tuesday that the youngest group of children has significant need for vaccine access, particularly given the omicron variant’s rapid spread and a related “notable rise in the number of hospitalizations in young children with severe disease.”
In Santa Clara County, just over 50% of children ages 5-11 are fully vaccinated, as are nearly 90% of teenagers, according to the county’s public health tally. Among adults, 93% have completed the primary series of vaccinations, and 65% added the third booster shot understood to prove particular protection against the omicron variant.
