Dr. Daniel Leonard, a pediatric hospitalist who is working on the Pfizer/BioNTech vaccine trial for these kids, said people are driving in from several states away to take part.
“We’re here in south central Nebraska, and while many may not think that this would be the epicenter of scientific progress, the influx that I’ve had with people from Colorado, Minnesota, Wisconsin, Iowa — some driving eight or nine hours each way overnight to participate in the study,” he said. “They are dedicated.”
Experts say the wait for a vaccine may not be much longer.
Pfizer CEO Albert Bourla said Sunday that he expects to have a vaccine for children 6 months to 4 years old “potentially in May, if it works.”
“And we will be ready with manufacturing,” Bourla added on CBS’ “Face the Nation.” Pfizer’s Covid-19 vaccine is already authorized for people as young as 5.
Johnson & Johnson, which makes the other Covid-19 vaccine authorized in the United States, has a late-stage trial of a vaccine for 12- to 17-year-olds but nothing for this younger group.
Waiting for more data
Initially, the Pfizer and BioNTech vaccine for this age group was being tested with just two doses, but the results weren’t what scientists had hoped for and the companies said they would test a third dose. But at the request of the FDA, the companies submitted a request for an emergency use authorization of two doses of the vaccine and said they would continue to test a third doses as the two doses moved through the regulatory process.
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n mid-February, the plan changed again. Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said the agency needed to see data from an ongoing trial of a third vaccine dose in these younger children in order to move forward with emergency use authorization. A February 15 meeting of the FDA’s Vaccines and Related Biological Products Advisory Committee was delayed.
Families would have to wait for the third-dose data after all.
“The immunogenicity analysis really showed that the immune response really wasn’t where it should be,” Dr. William Towner, who leads the Clinician Investigator Program for the Southern California Permanente Medical Group, said of the vaccine trials. “I think the data is pretty strong that for children, this will be a three-dose series.”
Two doses didn’t seem to do the trick, agreed Dr. James Versalovic, the pathologist-in-chief at Texas Children’s Hospital, where some Pfizer and Moderna pediatric trials are under way. “The data just weren’t as robust as we had hoped for in terms of immune response,” particularly with children in the 2 to 4 range.
Scientists working on the littlest kid trials have the benefit of observing what happens with other age groups. After seeing breakthrough infections in 2021, Versalovic said, scientists learned quickly that adults and adolescents needed booster doses.
“Taking these lessons to heart, we just pivoted in late December and just kept going forth full-tilt with a third dose and following these children during the trials,” he said. Children who have gotten a third dose need to be followed for at least two months before the data can be submitted to the FDA.
Investigators across the country confirmed that they are working as quickly and as carefully as they can to gather the data. Bourla said Sunday that the company should have data on its three-dose vaccine trial for this age group by April.
“The studies must be done correctly, and if it takes a bit longer, that’s OK; let’s do it right,” said Dr. Sharon Nachman, a pediatric infectious disease specialist at Stony Brook…
Read More: Where the US stands on Covid-19 vaccines for children under 5