Q: What does that mean for when my kid can get vaccinated?
A: It is true: Current Phase 3 trials do not include children, and it means we’ve got a longer wait for a vaccine approved for use in children.
We’ve covered a lot of vaccine development news on Dear Pandemic (see links below), but we haven’t addressed this important issue yet: When and how do we find out if the 40+ COVID-19 vaccines currently in Phase 1-3 trials can be given to kids? Do we have even more school disruptions ahead if kids can’t get vaccinated in 2021?!?
The vaccine development process starts with testing safety and efficacy in small scale Phase 1 and Phase 2 trials. Even for vaccines developed specifically for children (think measles, polio), they go in adult arms first before being tested in older and then younger children.
As Carl Zimmer wrote in a NYT article recently (linked below), “vaccine developers are keenly aware that children are not simply miniature adults.” Kids’ immune systems work differently than adults, and the vaccine dose that is right for an adult may have to be tweaked for children. (Interesting examples from Zimmer: kids get larger doses of the pertussis vaccine than adults do, but smaller doses of hepatitis B).
How does the Food & Drug Administration handle this issue in their vaccine approval process? Since 2005, the Pediatric Research Equity Act (PREA) has required that new biologics licensing applications or BLAs include a plan for studying the vaccine in a pediatric population. (Remember that “BLA” acronym, you’ll be hearing it a lot as COVID-19 vaccines go through the approval process; same with “EUA” or Emergency Use Authorization.)
In a recent Viewpoints article in the journal Clinical Infectious Diseases (linked below — it’s a great read), Emory University’s Dr. Evan Anderson and colleagues made a strong pitch to get Phase 2 trials in kids underway *now*. They argue that there is sufficient data from the Phase 1 and Phase 2 adult trials to safely proceed with trials in adolescents, and then in older and younger children. They review what’s known about the role of children in COVID-19 transmission, the burden of disease in children, the direct benefits and potential risks of vaccinating kids against SARS-CoV-2, and the risks of delaying approval of a pediatric vaccine (yep, including more remote school, sigh).
Importantly, they also note the *indirect* benefits that may accrue when children and adolescents are vaccinated. If you read our recent herd immunity post (linked below), you know that the way to crush this virus is to make sure that new cases of the disease can’t find any susceptible people to pass it on to. Vaccinated kids can play a crucial role in herd immunity, protecting older adults and medically vulnerable people. (A great example of this is the reductions in adult pneumococcal disease we saw once the pediatric pneumococcal conjugate vaccine was rolled out).
Bottom line: The route “back to normal” for kids likely includes a vaccine, and getting a safe vaccine for kids requires separate pediatric studies. The sooner those can start, the sooner we’ll have a pediatric vaccine.
And thanks to Colleen from Chicago for this Question Box query!
Viewpoint on “Why are children stuck in neutral?” https://bit.ly/3mXxL4Q
Our recent vaccine and herd immunity posts: