Shots for kids: Pfizer reports vaccine works on young teens
The Pfizer vaccine is safe and very effective against COVID19 in children as young as 12, according to early study results released by the manufacturer Wednesday that add to growing evidence that immunizations could be a major factor in fully reopening schools in the fall.
In its latephase study of children ages 12 to 15, the vaccine was 100% effective at preventing symptoms of COVID19, and no serious side effects were reported. The results have not yet been published or validated by independent scientists.
Pfizer, a U.S. pharmaceutical company that manufactures the coronavirus vaccine with Germanybased BioNTech, said it plans to apply “as soon as
possible” for emergency authorization, from the Food and Drug Administration, for 12 to 15yearolds. It’s already authorized for people 16 and older, and the 12to15 age group, if added, could get the vaccine by the end of summer.
The news about adolescents comes on the heels of confirmation from U.S. public health authorities that both the Pfizer and Moderna vaccines appear to be powerful at preventing disease transmission — a key issue that until recently had not been clear, with officials warning that even after vaccination people potentially could still infect others.
Taken together — along with expectation that vaccine supply will increase dramatically in the coming months — the updates this week should bolster confidence in vaccines overall, and in particular when it comes to reopening schools, infectious disease experts said. One concern repeatedly raised in returning children to classrooms is that vaccinated teachers and staff could pass the virus to students. That now seems unlikely.
And though vaccinations probably won’t be required for students before school starts this fall, they could be an important tool for reopening middle and high schools.
“I texted my daughter when I heard the news and she was very excited, and I’m excited. I think this is the next big step in what we need to do in this pandemic,” said Dr. Melanie Ott, a senior investigator at the Gladstone Institutes in San Francisco. Her daughter is 15 and has been in a hybrid virtual/inperson classroom since December.
Drugmaker Moderna also expects results in the coming weeks from its vaccine studies in younger teens. Both manufacturers have started studies in younger children, too, with results expected late this year or early 2022.
For inperson learning, the results in adolescents are key. Young children tend not to suffer serious illness from the coronavirus or widely transmit it. They also are thought to do less well with virtual learning than older students. So getting elementary school children back to classrooms has become an urgent matter, not dependent on vaccinating them.
Older children are somewhat more complicated, with illness and potential transmission rates more comparable to adults. Making vaccines available to high school and middle school students before they resume fulltime, inperson classes would be a comfort to educators and families, infectious disease experts said.
“This should take off the table everything preventing K12, inperson, five days a week learning in the fall,” said Dr. Monica Gandhi, a UCSF infectious disease expert who has been arguing strongly for schools to reopen right away. “I can’t see a single barrier.”
Pfizer’s latest study looked at 2,260 adolescents in a phase 3 clinical trial, the last step before applying for authorization. Eighteen COVID19 cases were reported, all in children who had received a placebo instead of the vaccine. Some experts said they would like to see results from a larger study group, especially with only 18 total infections reported. But it’s promising that no cases turned up in vaccinated children.
“100% (protection) is just absolutely amazing,” said Dr. Ken Grullon, physician in chief for Kaiser Permanente’s Diablo Service Area. He said he hopes for quick approval: “We can start over the summer and get kids vaccinated so that schools in ... August and September will just be at full strength.”
In addition, the vaccine prompted a very strong antibody response in children — even stronger than in 16 to 25yearolds. Pfizer did not provide details, but said side effects were not serious and were comparable to those seen in older teens and young adults.
Infectious disease experts also cheered the news this week that both the Pfizer and Moderna vaccines appear to be very good at preventing transmission. Early studies had found them to be up to 95% effective at preventing COVID19 symptoms, but did not determine whether vaccinated people could still become infected and pass the virus on to others.
Studies of the first groups of people immunized in the United States found the vaccines are about 90% effective at preventing infection of any kind, and therefore at stopping disease transmission, according to the Centers for Disease Control and Prevention.
“What we’re seeing is what we were hoping would be the best case scenario, that these two vaccines provide great protection against transmission,” said Dr. Yvonne Maldonado, an infectious disease expert at Stanford.
But she and Ott warned that even with strong protection against transmission, people need to remain wary for at least the next several weeks or months with so much of the population unvaccinated. That’s especially true as variants that may not be as responsive to vaccines start to circulate.
California now has 34 cases of the P.1 variant from Brazil and 10 cases of the B.1.351 variant from South Africa, both of which are somewhat resistant to antibodies. Those are still small numbers of cases, but they’ve been rising sharply over the past week, especially the P.1 variant, which is driving a deadly surge in Brazil.
“There’s no question we’re going into a fourth surge, but hopefully we can really, severely flatten it by having a sufficient degree of herd immunity,” Ott said.