After Pfizer’s COVID-19 vaccine earned full regulatory approval Monday, pressure is mounting to have the vaccine available to children under 12 years old—and so are concerns that it will be given to them prematurely.
The approval from the Food and Drug Administration covers use of the vaccine in people ages 16 and up, while the agency’s Emergency Use Authorization still allows for its use in adolescents between the ages of 12 and 15. Some experts expect the FDA will grant full approval for use in 12- to 15-year-olds relatively soon.
But many parents and pediatricians are most eager for the green light to offer the vaccine to children under 12. Vaccinating young children has become a particularly pressing issue with the wild spread of the hypertransmissible delta variant, new school terms beginning, disputes over masks, and big holidays just around the corner. In a letter sent to the FDA earlier this month, the American Academy of Pediatrics urged the agency to authorize the vaccine for children under 12 “as swiftly as possible.”
For now, the FDA is awaiting data on which to base a decision. Clinical trials in children ages 5 to 11, 2 to 5, and 6 months to 2, are still ongoing. The trials will provide critical data on vaccine safety and what dosages provide optimal immune responses in each age group. The trials included multiple dosage options for each age group.
US officials have offered slightly different estimates for when the vaccines will get the go ahead from the FDA. In a Tuesday morning interview with the Today, top infectious disease expert Anthony Fauci said vaccines for kids under 12 will be available “hopefully by the mid-late fall and early winter.”
Meanwhile, Francis Collins, director of the National Institutes of Health, offered a slightly longer timeline in an interview with NPR’s Morning Edition, also on Tuesday. “I don’t see the approval for kids 5 to 11 coming much before the end of 2021,” he said.
The FDA’s decision could have potentially come earlier, however. Last month, the FDA urged Pfizer and its partner BioNTech, as well as Moderna, to boost the size and design of their trials to be better able to detect potential rare side effects, particularly myocarditis, or inflammation of the heart muscle. Data from older groups suggested that myocarditis is a rare, though generally mild, side effect of the mRNA-based COVID-19 vaccines, which includes the Pfizer/BioNTech and Moderna vaccines. The risk is low, with one estimate at about 13 cases after a million vaccine doses administered. But the risk appears greatest, so far, in young males ages 12 to 17.
In the AAP’s letter to the FDA earlier this month, the doctor’s group wrote that it appreciated the FDA’s rigorous commitment to review safety but said the expansion of the trials shouldn’t delay authorization.
“In our view, the rise of the delta variant changes the risk-benefit analysis for authorizing vaccines in children,” the AAP wrote. “The FDA should strongly consider authorizing these vaccines for children ages 5-11 years based on data from the initial enrolled cohort, which are already available, while continuing to follow safety data from the expanded cohort in the post-market setting. This approach would not slow down the time to authorization of these critically needed vaccines in the 5–11-year age group.”
In pressing its case that the FDA should move faster, the AAP noted that children have historically made up about 14 percent of COVID-19 cases in the pandemic, but the share of pediatric cases has recently grown, reaching 19 percent for the week ending July 29. “The higher proportion of cases in this population means this age group could be contributing in driving continued spread of COVID-19,” the AAP wrote. Though children have relatively low risks of severe disease and death from COVID-19, the group noted that “[s]adly, over 350 children have died of COVID since the start of pandemic, and millions of children have been negatively impacted by missed schooling, social isolation, and in too many cases, the death of parents and other caregivers.”
For now, the FDA says it’s still waiting for data on safety, dosage, and efficacy. In a press briefing Monday, acting FDA Commissioner Janet Woodcock said that the agency just didn’t have the data to make any decisions and that the vaccines shouldn’t be used in children until that data is available and reviewed. “We need to get the information and data on uses in younger children,” she said. “They are not just small adults, and we’ve learned that time and time again.”
On this point, the AAP agreed and warned against jumping the gun on use in children. With the approval of the Pfizer/BioNTech vaccine Monday, the AAP along with many parents and doctors raised questions and concerns of off-label use, i.e., doctors offering the vaccines to those under 12 despite age limitations for the approval and authorization.
Normally, doctors have leeway to use approved drugs in unapproved ways. But because the COVID-19 vaccines are distributed through the federal government, anyone administering the vaccines must adhere to a provider agreement with the Centers for Disease Control and Prevention, which prohibits off-label use. If any pediatricians go rogue and decide to offer vaccines to those under 12 anyway, they may be on the hook for administrative costs, they may lose liability coverage, and they may lose the ability to provide the vaccines altogether.
But most importantly, doctors shouldn’t go off-label because it’s not in the best interest of younger patients, the AAP argued Monday.
“The clinical trials for the COVID-19 vaccine in children ages 11 years old and younger are underway, and we need to see the data from those studies before we give this vaccine to younger children,” AAP President Lee Savio Beers said in a statement Monday.
Dr. Yvonne Maldonado, chair of the AAP Committee on Infectious Diseases, also weighed in, saying: “We do not want individual physicians to be calculating doses and dosing schedules one-by-one for younger children based on the experience with the vaccine in older patients. We should do this based on all of the evidence for each age group, and for that we need the trials to be completed. I know parents are anxious to protect their children, but we want to make sure children have the full benefit of ongoing clinical trials.”
In his NPR interview Tuesday, Dr. Collins echoed the point while urging patience on getting the trial results. “It’s a difficult situation,” he said, “because kids under 12 are not just little miniature human beings. They have differences in their metabolism, their immune system.”