FDA on Monday amended the emergency use authorization for Pfizer's Covid-19 vaccine to allow the use of the vaccine in children ages 12 to 15, a decision that President Joe Biden praised as a "promising development" in the fight against Covid-19.

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Details on the authorization

The authorization comes following a clinical trial of the vaccine in 2,260 adolescents ages 12 to 15. In the trial, 1,131 participants received the vaccine and 1,129 received a saline placebo.

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The trial found the vaccine was 100% effective at preventing Covid-19 among the participants, with no participants in the vaccine group developing Covid-19 compared with 18 in the placebo group. The trial also found that the adolescents developed even higher levels of antibodies post-vaccination than adults did.

Bill Gruber, an SVP at Pfizer and a pediatrician, said the results from the trial were a "trifecta" of good news. "We have safety, we got the immune response we wanted—it was actually better than what we saw in the 16- to 25-year-old population—and we had outright demonstration of efficacy."

Following the authorization, CDC's Advisory Committee on Immunization Practices is scheduled to meet Wednesday to vote on recommending the vaccine to 12 to 15-year-olds.

If the committee votes to recommend the vaccine, Peter Marks, the top vaccine regulator at FDA, said shots could be ready to be administered as soon as Thursday. President Biden has previously said around 20,000 pharmacies are prepared to administer the vaccine to adolescents.

However, Marks and Janet Woodcock, acting FDA commissioner, have said regulations at the state level may affect where adolescents can get vaccinated.

"We don't regulate the practice of medicine at FDA, we regulate these products," Marks said. "How they are administered may be regulated different in some states in terms of who can give a vaccine to a 12-year-old."

'This is exciting news'

Numerous public officials and health experts said FDA's authorization is a step forward in fighting the Covid-19 epidemic.

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"The light at the end of the tunnel is growing, and today it got a little brighter," President Biden said. He added, "If you are a parent who wants to protect your child, or a teenager who is interested in getting vaccinated, today's decision is a step closer to that goal."

FDA's decision "is a significant step in the fight against the Covid-19 pandemic," Woodcock said. "Today's action allows for a younger population to be protected from Covid-19, bringing us closer to returning to a sense of normalcy and to ending the pandemic."

"This is exciting news," NIH Director Francis Collins said. "We know that a million-and-a-half adolescents have been infected with Covid-19 since this pandemic started, and not all of them have fared as well as most. And some of them have ended up with this long Covid where they're not better, even weeks or months after getting ill, so we really want to protect adolescents."

Education leaders and school superintendents said the decision could also boost efforts to reopen schools full-time for middle and high school students this fall.

"The vaccination is the ticket for the most normal school year possible next year," Scott Brabrand, superintendent for Fairfax County Public Schools in Virginia, said.

However, one major hurdle to widespread vaccination of adolescents is that, according to polling data from Axios and Ipsos, parents are split almost 50-50 on whether they'll allow their children to get vaccinated.

We will need parent buy-in," Donna Hallas, a pediatrician and director of the pediatric NP program at the NYU College of Nursing, said. "If they're hesitant people or refusers for previous vaccines, this is a really tough job that health care providers need to address."

Christoph Diasio, a pediatrician at Sandhills Pediatrics in North Carolina, said he believes primary care providers will play a significant role there.

"We feel that primary care is going to have a real role with the folks who are a little bit hesitant or just need some questions answered," he said. "Maybe the community, for whatever reason, trusts their family doctor of their pediatrician more than they trust, for example, a corporate pharmacy" (Hopkins et. al., Wall Street Journal, 5/10; Morello/Lim, Politico, 5/10; Mandavilli, New York Times, 5/10; FDA release, 5/10; DeCiccio, CNBC, 5/10; Owens, "Vitals," Axios, 5/11; Mascarenhas, CNN, 5/10).