Moderna revealed on Thursday that it has asked the US Food and Drug Administration to grant emergency use authorization for its COVID-19 vaccine for children under 6 years old.

The Washington Post reports:

The path to a vaccine for the youngest children has been tortuous, marked by disappointing results, delays and confusing communication — and in the meantime, as many as 75 percent of children have been infected with the virus since the dawn of the pandemic, according to a new study.

Moderna’s announcement will intensify pressure on the Food and Drug Administration to move quickly, as parents, pediatricians and politicians have become increasingly impatient about the lack of vaccines and treatments to protect young children.

CNN adds:

In late March, Moderna announced results of a clinical trial that included 2,500 children ages 6 months through 24 months and 4,200 children ages 2 through 5. The company said that two 25-microgram doses of its vaccine led to a similar immune response in young children as two 100-microgram doses for adults ages 18 to 25. And it said this should predict protection from Covid-19 and severe Covid-19 down to 6 months of age.

In Thursday’s news release, the company said the data showed “a robust neutralizing antibody response” and “a favorable safety profile.”

“We like to see anything above 1,000 units, and what we, in fact, saw here are levels somewhere between 1,400 and 1,800 units,” Dr. Paul Burton, chief medical officer of Moderna, said Wednesday. “So that’s extremely reassuring.”

From The Associated Press:

“There is an important unmet medical need here with these youngest kids,” [Burton said]. Two kid-size shots “will safely protect them. I think it is likely that over time they will need additional doses. But we’re working on that.”

Now, only children ages 5 or older can be vaccinated in the U.S., using rival Pfizer’s vaccine, leaving 18 million younger tots unprotected.

Moderna’s vaccine isn’t the only one in the race. Pfizer is soon expected to announce if three of its even smaller-dose shots work for the littlest kids, months after the disappointing discovery that two doses weren’t quite strong enough.

The New York Times provides key context:

So far, Moderna’s vaccine has been cleared only for adults. The F.D.A. has generally authorized Covid vaccines according to age group, calculating that the risks of severe disease and the benefits of vaccination are highest for the oldest Americans and reduced for young recipients. Moderna has also requested authorization of its Covid vaccine for 6- to 11-year-olds and 12- to 17-year-olds, and a spokeswoman said that it would submit data rounding out those requests in about two weeks.

At a Senate oversight hearing on Tuesday, Dr. Peter Marks, who oversees vaccine regulation for the F.D.A., hinted that the agency might consider Moderna’s applications for everyone under 18 as a whole. Some requests “are complicated because they are relatively larger, covering larger swaths of the pediatric population than others,” he said in response to a senator’s question about when a pediatric vaccine would be ready.

Meanwhile, on Tuesday Pfizer asked the FDA to authorize a booster shot of its COVID-19 vaccine for children five through eleven.

“Studies have shown that vaccine efficacy has waned significantly in this age group during Omicron,” reports CNN.