WASHINGTON — An expert committee advising the Food and Drug Administration on Tuesday recommended that regulators authorize Pfizer-BioNTech’s coronavirus vaccine for 5- to 11-year-olds, bringing about 28 million children a major step closer to becoming eligible for shots.
If the F.D.A. follows the panel’s advice in the coming days, as is expected, the Biden administration will have expanded vaccine access to all but the youngest Americans, while providing booster shots for many as well.
Biden administration officials see the pediatric dose as crucial to keeping schools open and restoring a sense of normalcy to family and work life as the pandemic hurtles toward the end of its second year. The administration wants to be seen as doing everything possible to combat the virus and build upon positive trends, as the Delta variant ebbs and the daily drumbeat of infections and deaths fades.
Younger children would start getting their shots at a time when coronavirus cases are dropping sharply. But public demand for a pediatric vaccine has been high, and some panel members said that even though young children are less likely to get severely ill from Covid-19, parents and doctors alike are anxious to protect them.
Dr. Jay Portnoy, a medical director at Children’s Mercy Hospital in Kansas City, Mo., said he had seen critically ill children in the intensive care unit and “terrified” parents. “I’m looking forward to being able to actually do something to prevent that,” he said.
The vote was 17-0 in favor, with one abstention. Federal regulators and scientists made a strong push, arguing that 8,300 children between 5 and 11 had been hospitalized with Covid-19 and nearly 100 had died over the course of the pandemic.
Covid-19 is “the eighth-highest killer of kids in this age group over the past year,” said Dr. Amanda Cohn, a top C.D.C. vaccine official. “Use of this vaccine will prevent deaths, will prevent I.C.U. admissions and will prevent significant long-term adverse outcomes in children.”
Data from Pfizer showed that the vaccine had a 90.7 percent efficacy rate in preventing symptomatic Covid-19 in a clinical trial of 5- to 11-year-olds. Still, many advisory committee members expressed concern about limited safety data, turning repeatedly to the risk of myocarditis, a rare condition involving inflammation of the heart muscle, in young vaccine recipients. Myocarditis and pericarditis, inflammation of the lining around the heart, have been tied to the Pfizer-BioNTech and Moderna vaccines, particularly in younger men.
The Pfizer dose for younger children would be one-third of the strength given to people 12 and older, with two shots given three weeks apart. Experts have said that could diminish the risk of the heart-related side effects.
If F.D.A. regulators follow the committee’s advice, as they typically do, an authorization could come within days. The Centers for Disease Control and Prevention’s own panel of outside experts is scheduled to meet Tuesday and Wednesday, and is also expected to endorse a pediatric dose. The C.D.C., which sets vaccine policy, would likely then quickly recommend the rollout of shots.
During a long debate before the vote, some committee members questioned whether every child in the age group really needed the vaccine or whether it should be limited to those at high risk of severe Covid-19 — an easily identifiable group, with underlying conditions such as obesity or other risk factors.
Dr. James E.K. Hildreth, the president and chief executive of Meharry Medical College, said that since many children between 5 and 11 may already have some immunity after contracting the virus, the need to vaccinate broadly in the age group might be less urgent.
“It just seems to me that in some ways we’re vaccinating children to protect the adults, and it should be the other way around,” he said. “I do believe that children at highest risk do need to be vaccinated. But vaccinating all of the children to achieve that just seems a bit much for me.”
Dr. Hildreth also bemoaned the fact that Pfizer’s pediatric trial included few children from minority groups, who are at greater risk of bad outcomes from Covid-19.
While some committee members said they wished to recommend the vaccine for a more narrow group of children, they were asked to decide simply whether the benefits of a pediatric shot outweigh the risks. “We decided to go for it with a lot of heavy conscience,” said Dr. Eric Rubin, an infectious diseases expert at the Harvard T.H. Chan School of Public Health.
Dr. Paul Offit, a panel member who heads the Vaccine Education Center at Children’s Hospital of Philadelphia, said it was “nerve-racking” to make public health decisions affecting millions of children based on studies involving just a few thousand participants.
But he said: “The question is, when do you know enough? And I think we certainly know that there are many children between 5 and 11 years of age who are susceptible to this disease who could very well be sick and or hospitalized, or die from it.”
Dr. Peter Marks, who heads the agency’s division that oversees vaccine approvals, told the committee that nearly two million in that age group have been infected, and that a third of those hospitalized have needed intensive care.
Committee members said they hoped a pediatric dose would not only keep elementary schoolers out of the hospital, but would reduce transmission of the virus and cases of long Covid.
Dr. Fiona Havers, a viral disease specialist at the C.D.C., told the panel that more than 2,000 schools had been forced to close between early August and October because of outbreaks, affecting more than a million students.
Children have higher levels than adults of the neutralizing antibodies that are essential for preventing infection, she said, but are at least as likely as adults to be infected, she said. She said there appear to be many more cases of child infection than are publicly recorded.
Covid-19 hospitalization rates in the 5 to 11 age group are three times as high for Black, Hispanic and Native American children as for white children, Dr. Havers added.
The C.D.C. also presented data on blood samples from young children indicating that 42 percent had coronavirus antibodies, raising questions about whether many had been infected with no symptoms and developed natural immunity. Dr. Havers cautioned that the children tested were already under clinical care and may not represent the general pediatric population.
“We saw the highest hospitalization rates in the 5- to 11-year age group in September, during the Delta wave,” she said. “There’s clearly a lot of susceptible children still out there that are vulnerable to severe disease.”
It is unclear how many parents would quickly vaccinate their elementary schoolers if given the chance. Polling has showed that roughly a third are eager to do so right away, while a third prefer to wait. Since federal regulators cleared Pfizer shots for adolescents ages 12 to 15 in May, 46 percent have been fully vaccinated, compared with about 69 percent of adults.
Many panel members said the data on safety and efficacy was compelling enough for government to offer shots and give parents a choice.
But Dr. Michael G. Kurilla, an official at the National Institutes of Health who abstained from the vote, said the government was embracing a “one-size-fits-all” approach.
“I think for many children who have experienced Covid already, they’re probably more than adequately protected. One dose may be sufficient,” he said. “I think for the high-risk children, it’s very different.”
The vote took place in a highly charged atmosphere. As of early Tuesday, nearly 140,000 public comments had been formally submitted to the agency on the issue. By contrast, only 66 comments were submitted before the panel recommended boosters for adult recipients of the Moderna and Johnson & Johnson vaccines.
Over the weekend, panel members were deluged with messages in an organized email campaign urging them to vote against recommending authorization. The C.D.C. warned members of its own expert panel Tuesday afternoon that they might be targeted by a similar “misinformation campaign.”
Dr. Marks said that while the public had “strong feelings” about authorization, the committee was only being asked whether to allow shots, not whether to mandate them.
But Dr. H. Cody Meissner, a panelist and chief of the pediatric infectious diseases division at Tufts Children’s Hospital, said he feared that state-level mandates would follow too quickly, before sufficient safety data could be gathered. And others questioned how well the government tracks adverse side effects, despite assurances that any worrisome patterns would be detected.
F.D.A. scientists said the benefits of staving off Covid-19 with a pediatric dose generally outweighed the risks of the most worrisome side effects. Even in a scenario where the risk of infection was low, as in June, the vaccine’s benefits may be greater because those hospitalized with Covid-19 tend to be sicker, and for longer, than those with myocarditis triggered by the vaccine, they said.
Pfizer officials described safety data on about 4,500 children ages 5 to 11 divided into two cohorts of roughly equal size. The first group was followed for about two months, the second for about two and a half weeks. None of the children involved in Pfizer’s clinical trial developed myocarditis or pericarditis, but that was expected given the small size of the clinical trial and the rarity of those conditions.
Federal health officials have said that cases of the heart conditions tend to be mild and resolve quickly, and that younger people can also develop myocarditis from the virus itself.
Pfizer tried to reassure the panel that pharmacists and other providers would be able to handle children’s shots. They would be color coded to reduce the risk of a mix-up, company officials said.
Apoorva Mandavilli contributed reporting from New York and Carl Zimmer from New Haven, Conn.