After Pfizer announced Sept. 20 that its COVID-19 vaccine was safe for children ages 5 to 11, Boston-area medical experts reacted with cautious optimism.
The company then said Tuesday it has submitted data on its study to the Food and Drug Administration, which is expected to take several weeks to analyze the findings before it would grant emergency use authorization for the age group.
Dr. Shira Doron, the hospital epidemiologist and antimicrobial steward at Tufts Medical Center, called the announcement “great news” but added, “What we have so far is just a press release. I certainly have not gotten my hands on data to review.” Still, she said, “everything in the press release looks great.”
Similarly, said Dr. Ofer Levy, director of the Precision Vaccines Program and senior physician in pediatrics in the Division of Infectious Diseases at Boston Children’s Hospital, “I welcome the news. I suspend final judgment until we see the data.”
Pfizer made its announcement following a Phase 2/3 study in which two-shot vaccines were administered to 2,268 children ages 5 to 11. Each received a combined dose of 10 micrograms, which was one-third the 30 micrograms given to adults ages 16 to 25 in a separate study.
A month after the second dose, the study reported that the children showed “a strong immune response.” The study also noted that among the children, “the COVID-19 vaccine was well tolerated, with side effects generally comparable to those observed in participants 16 to 25 years of age.”
“Having trials to prevent coronavirus infection, COVID disease, is obviously important to addressing the pandemic,” Levy said, “and children, although they are lower-risk than older adults for severe COVID, they can get infected, develop symptoms, [get] hospitalized.” Although children who die from COVID-19 are rare, unfortunately a few hundred have died in the US, he added.
“I think, for the most part, the assumption is that children transmit like adults do,” Doron said. “There may be differences. Little babies don’t cough very hard. Those differences are probably outweighed by the fact that guys carry little babies around, close to the face. Children transmit to adults, adults transmit to children.” She added that children are “less likely to get tested.”
At-home testing for children is “pretty easy,” she said, with “fairly easy-to-follow instructions,” although “it’s not very cost-effective. We really do need low-cost at-home testing, for sure.”
And, she said, she has been getting questions about the dosage administered to children: “A lot of people ask me, ‘is the one-third dose OK? What about an 11-and-a-half-year-old who is the same size as a 12-year-old? Should they really be given the one-third dose?’ I want to see the breakdown in outcomes by weight, height, all of these things. It’s really early to make a lot of conclusions.”
The information is expected soon. In a television interview that aired Sept. 26, Pfizer CEO Albert Bourla said “it’s a question of days, not weeks” before data on the children’s vaccine is submitted for federal authorization.
Vaccine stances were challenged in another way Sept. 17 when an FDA advisory panel voted 16-2 to oppose booster shots for everyone age 16 and over, which had been a goal of the Biden administration. Levy, a member of the panel, was among those voting against boosters for everyone.
“It’s unusual to have a question voted down by such a margin,” Levy said.
Reflecting on the vote, he said, “We felt at the time there was insufficient evidence regarding the safety. It’s not like there’s some bad safety, there’s not evidence of some terrible side effects detected in younger age groups.
“We might eventually go in that direction [of supporting boosters].”
What the panel did was rephrase the issue for another vote, on whether to recommend boosters for older Americans ages 65 and older and individuals at high risk for COVID-19 based on underlying medical conditions or line of work. The panel unanimously voted 18-0 to recommend boosters for these populations.
“The panel’s recommendations were pretty good,” Doron said. “I think the FDA panel is really charged with [asking] ‘Does the safety and effectiveness data, does the observable data on infections support boosters for all Americans?’ It did not.”
She noted that the rephrased question and second vote happened in “a really unprecedented way.”
Doron questioned the wording of the term “occupational exposure” as a risk factor for COVID-19, which has been cited by both the FDA panel and by Centers for Disease Control and Prevention head Dr. Rochelle Walensky.
“The intent is right, the wording is wrong,” Doron said. “Perhaps, I think, critical infrastructure workers.”