If Pfizer's data pans out, when will little kids get the COVID-19 vaccine?

A third pediatric dose of the Pfizer-BioNTech COVID-19 vaccine in children 6 months to under 5 years of age prompted a strong immune response, with a safety profile that was similar to placebo, the companies said.

Pfizer's pediatric COVID-19 vaccine has an efficacy of 80.3%, according to a preliminary analysis, and meets "all immunobridging criteria required for Emergency Use Authorization," the company said Monday. The results are based on clinical trials in which kids from six months to age 5 got three doses of the company's vaccine.

Pfizer and its partner, BioNTech, plan to submit the new data to the Food and Drug Administration this week, bringing families with young children one step closer to a long-awaited vaccine.

Also on Monday, the FDA updated the schedule for its vaccine advisory committee, saying it will meet to discuss pediatric COVID-19 vaccines on June 15.

The regimen has three doses

The size of Pfizer's pediatric dose is one-tenth of its adult dose. The company had originally tested a two-dose regimen, but mixed results prompted Pfizer to test a three-dose regimen.

The third dose was "well tolerated among 1,678 children under 5 years of age with a safety profile similar to placebo," Pfzier said as it announced the news.

Kids in the trial received the third shot at least two months after their second dose, the company said, adding that at the time of the vaccine trial, omicron had become the predominant COVID-19variant in the U.S.

So, when could little kids get the vaccine?

Pfizer announced its findings two weeks before what had been FDA's earliest date for to start the review process for young kids' vaccines. The agency had set aside three dates in June for its independent advisory panel to meet and discuss pediatric vaccines: June 8, 21 and 22.

But the FDA updated that schedule on Monday, saying the influential Vaccines and Related Biological Products Advisory Committee, or VRBPAC, now plans to meet on June 15 to discuss vaccinations for kids as young as 6 months.

The VRBPAC will consider applications from both of the makers of the most common COVID-19 vaccines in the U.S.: Moderna asked the FDA last month to authorize a low-dose form of its vaccine for younger children.

Kids from ages 5 to 11 have been eligible for the COVID-19 vaccine since last November. For hints about when younger kids might be able to receive the vaccines, here's a look at how that earlier process played out:

Oct. 7: Pfizer formally asked the FDA for Emergency Use Authorization of its vaccine for children ages 5 to 11, after saying it was found to be safe and effective;

Oct. 22: The FDA released the companies' briefing documents, as well as its own analysis;

Oct. 26: FDA advisory panel recommended Pfizer vaccine for kids ages 5 to 11

Nov. 2: The CDC recommended Pfizer's vaccine for the age group; it becomes widely available within one week afterward.

If the VRBPAC agrees with Pfizer's findings and that timeframe is repeated, it's possible that toddlers, preschoolers and new kindergarteners could be eligible to receive the vaccine within the first weeks of the summer.

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