'Not typical': FDA takes unusual step in urging Pfizer to seek approval for child vaccine
In a move that highlights rising concerns about the risks of COVID-19 to younger children, Pfizer-BioNTech has asked for federal authorization for its vaccine for children 6 months to 4 years old.
Companies usually make the decision to submit a request to Food and Drug Administration on their own, but in this instance it was made at the urging of the federal agency.
"That’s not typically the way the federal government works. Usually, they wait and let the company decide when it wants to submit," said Dr. Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia.
The FDA said concerns about children were behind Tuesday's request.
Early on in the pandemic, younger children were less likely to become severely ill with COVID-19, but the emergence of new variants is “having a much greater toll on children,” the agency said in a statement to USA TODAY.
“In light of these new data and the rise in illnesses and hospitalization in this youngest age group, FDA believed that it was prudent to request that Pfizer submit the data it had available, including the data that it has recently collected during the omicron surge,” the statement said.
Parents and doctors are eagerly awaiting the day the vaccine can be given to the youngest children. If it is approved, Pfizer would be the first for this age group.
A third low-dose shot probably would be needed in younger children to boost the vaccine's effectiveness.
"Almost certainly, if this is authorized, there will be consideration of a third booster dose a couple of months later that could lead to even stronger protection, including against mild and serious infection," said Dr. Mark McClellan, former FDA commissioner and now founding director of the Duke-Margolis Center for Health Policy at Duke University.
The FDA will review the data, and then independent expert advisory committees for the FDA and the Centers for Disease Control and Prevention will review it, McClellan said. "So, there are lots of opportunities coming for parents and their pediatricians to see all the data on safety and effectiveness before making a decision."
Cases of COVID-19 in children have topped 10 million. In January, pediatric hospitalizations for COVID-19 were at their highest rate ever in the pandemic. As of Jan. 26, 280 children in the United States ages 4 and under had died of COVID-19, according to the CDC.
Having the FDA ask a company to make a submission is certainly "unusual," said Glen Nowak, director of the University of Georgia's Center for Health and Risk Communications and a former communication director for the National Immunization Program at the CDC.
"But then, the pandemic has been unusual. We've had so many things happen that have never happened before," he said. "In the context of the pandemic, it probably makes sense that the FDA would be encouraging manufacturers who have promising vaccines to make those things available as fast as they possibly can assuming they’re safe and effective."
How effective will a vaccine for younger children be?
The Pfizer vaccine would be given in a low-dose format for younger children, and the dose would depend on age. Everyone 12 and over gets a 30-microgram dose. Children 5 and older get a 10-microgram dose. If the new vaccine proposal is approved, children under 5 would receive a 3-microgram dose.
For now, Pfizer's request is that the FDA issue an emergency use authorization for a two-dose vaccine series, even though the company is conducting clinical trials for two doses plus a third booster shot.
In late December, Pfizer said two doses in 2- to 4-year-olds had not been shown to be effective against COVID-19. The children in the trial did not mount enough of an immune response to suggest they would be protected against severe disease.
But children ages 6 months to 2 years did show an adequate immune response.
The question now is whether the two-dose series is effective enough to meet the FDA's original bar for approval of being at least 50% more effective than a placebo in preventing COVID-19 or decreasing the severity of the disease.
Data on a booster dose given eight weeks after the initial two-dose series "are expected in the coming months and will be submitted to the FDA to support a potential expansion of this requested EUA," Pfizer said in a statement.
The FDA's Vaccines and Related Biological Products Advisory Committee will meet Feb. 15 to discuss the data Pfizer has presented on the two-dose series.
The committee can't make any recommendations on a three-dose series because it won't be seeing those results yet. Any decisions "will depend on what data we see," said Offit, who sits on the committee.
The situation is similar to that faced by the Johnson & Johnson vaccine when it was first presented to the committee.
"J&J asked for approval of a one-dose vaccine while they were in the midst of clinical trials for a booster dose," Offit said. Eventually, that data was submitted and the FDA approved a one-plus-booster regimen for J&J.
By allowing two doses of the Pfizer vaccine for younger children in the near term, a third dose could be available sooner. A third dose is in clinical trials now, and health officials believe it may provide a stronger immune response. The company said last month that those trials would be complete by late April or early May.
Eager to get started
Dr. Stan Spinner is happy the FDA and companies are moving forward and eager to get younger kids vaccinated – starting with his two granddaughters, who were volunteers in the research trial.
"I don't see any reason to wait. I'm very very comfortable with the safety data," said Spinner, chief medical officer and vice president of Texas Children’s Pediatrics & Texas Children’s Urgent Care in Houston.
Although most younger children recover from a coronavirus infection just fine, a small percentage end up with severe COVID-19 or lingering symptoms, he said.
The shots won't prevent all disease, but they will "keep it to a cold rather than being out of school for two weeks or hospitalized," Spinner said.
Vaccinating younger children will also help slow the pandemic, he said. People who are vaccinated, even if they get infected, shed less virus for less time and so are less likely to infect others.
Two low-dose shots will at least start protecting the younger age group, said Spinner, who expects a third will be needed to provide full benefit. "Two doses will give reasonable, just not optimal protection," he said, but it makes sense "to get that started and not continue to delay."
Pfizer-BioNTech tested the higher, 10-microgram dose in toddlers but found that many spiked fevers. With the lower dose, Spinner said, "pretty much all the fevers went away. They just wiped out pretty much any of these reactions, which was great."
Every medical intervention has the potential for side effects, Spinner said, but those risks are tiny compared with the known problems COVID-19 can cause.
"I trust these vaccines and I have zero concerns about the safety," he said.
Contributing: Karen Weintraub
This article originally appeared on USA TODAY: FDA tells Pfizer to seek approval for COVID vaccine for kids under 5
