‘Tweenagers’ next frontier for vaccine trials
Twelve-year-olds are tween-agers, staring down puberty and middle school, surprisingly mature one minute and tortured by angst the next.
Some also are scientific pioneers, volunteering for clinical trials to test COVID vaccines in children. Slowly and gingerly, researchers are testing COVID-19 vaccines in younger and younger kids — even as millions of doses are pushed into the arms of their parents — with an eye toward FDA approval in the next year or two.
“People try to minimize how sick kids get with COVID, but that’s a mistake,” said Brigham C. Willis, senior associate dean for medical education and professor of pediatrics at UC Riverside’s School of Medicine. “I work intensive pediatric care, and there’s a minority who get extremely ill. There are some deaths. It’s not a non-entity.
“And even though a large majority of kids won’t get extremely ill, they can still contract and spread it. To get control of the pandemic, you have to vaccinate both adults and children.”
More than 300,000 coronavirus cases involving children younger than 17 have been reported in California since the pandemic began — more than 12 percent of the total. There have been six deaths — one child younger than 5, and five ranging in age from 5 to 17, according to state data.
One of them died in Los Angeles in December from mult-isystem inflammatory syndrome, or MIS-C, an extreme immune reaction linked to COVID. Another died this month in Stanislaus County.
“There have been deaths among kids with no highrisk factors,” said Grace Lee, professor of pediatrics at Stanford University School of Medicine and chief medical officer for practice innovation and infectious diseases physician at Stanford Children’s Health. “Sometimes we forget about it with the flu, but every year, kids die. About half had no serious underlying conditions. These are deaths that could have been prevented if we used all the tools in our tool kit to prevent unnecessary infection.”
With COVID, most critically ill kids seem to do OK over time, but the long-term side effects of the disease are still unknown, she said. “There’s a lot still to worry about. If it’s a preventable disease, why not use all your tools to prevent infection in those kids?”
Vaccine skeptics have a long list of reasons, but that battle looms on the horizon. Meantime, there’s great optimism that school will look nearly normal come the fall — long before vaccines are green-lighted for kids, and long before any COVID vaccination mandates that might follow.
Eventually, infants will be protected by antibodies from their vaccinated mothers, and the under-1 set by having adults in the household vaccinated, he said. But experts need to know if the vaccine protects schoolage children against disease or infection or both. And, if high schools are to return to something resembling normal soon, 16-, 17- and 18-year-olds must be bumped up the vaccine priority list. They’re more prone to illness than the youngest children, and Moderna’s vaccine already has emergency approval for that age group.
If it strikes you that clinical trials proceed at a much slower pace for kids than for adults, you’re correct.
“They’re a vulnerable population — we try to be extra careful with any research study involving children,” said UCR’s Willis. “You’re introducing a vaccine that’s intended to prevent harm, but it has risks, and you’re introducing it to a very healthy population.”
Researchers begin with very low doses and ramp up to determine the optimal dose that delivers the desired protection, he said.
“There’s a lot of work ahead,” said Stanford’s Lee. “I really would love them to begin clinical trial in the younger child population — we’re going to need to have that data. Is it safe? What are the efficacy considerations? I’m not a trialist and I know there are complicated considerations, but yes, I want it to move more quickly.”
Trial data from adults show that the vaccines are extraordinarily protective, and now that millions and millions of doses are going into adult arms, “we are going to have amazingly strong safety data in a pretty short time,” Willis said.
There’s no reason to think efficacy will be much different for children, but full FDA approval is likely years away nonetheless, he said. The virus will be waiting.
“It’s not likely that COVID is going to be eradicated from the earth,” Willis said. “There’ll have to be ongoing immunization efforts throughout the world, and kids will be a big part of that.”
He expects COVID vaccines will eventually be required to attend school — but not until after full FDA approval, which is quite a ways off.