Smaller doses of Pfizer's COVID-19 vaccine for children ages 5 to 11 appear safe and are nearly 91 percent effective at preventing symptomatic disease, the company said in a study released Friday.
Pfizer's study was released ahead of a pivotal Food and Drug Administration (FDA) advisory panel meeting Oct. 26, where regulators will discuss whether to recommend authorizing the vaccine for younger kids.
The FDA will post its own analysis of Pfizer's safety and efficacy data later on Friday.
If the panel votes favorably, and the agency accepts the recommendations, the Centers for Disease Control and Prevention (CDC) will make the ultimate decision on who should get the shots; the FDA determines safety and efficacy, while CDC regulates the actual practice of medicine.
If the vaccine is authorized, children could begin getting immunized in early November, with both doses completed in time for Christmas for the earliest ones in line.
The Biden administration has already purchased enough doses for the 28 million children who would be eligible if the vaccine is authorized. Distribution will rely on more than 25,000 pediatrician's offices, community health centers, schools and pharmacies.
According to the company, two 10-microgram doses administered three weeks apart offer similar protection against both the original strain and the delta variant of the virus.
Even though the dose was smaller, Pfizer's study found young children showed antibody levels just as strong as people who got a regular-strength dose.
Pfizer's vaccine is already authorized for adolescents over 12 years old, and approved for anyone over 18, but many parents have been waiting anxiously for the ability to protect younger children, especially as the delta variant has proved far more contagious and dangerous for them.
Although the mortality rate for COVID-19 in children is substantially lower than that in adults, COVID-19 was among the top 10 leading causes of death for children ages 5 to 14 between January and May 2021, according to Pfizer.
According to the CDC, COVID-19 has killed more than 630 Americans under the age of 18. Nearly 6.2 million children have been infected with the coronavirus, according to the American Academy of Pediatrics, with more than 1 million in just the past seven weeks.
In the study, three children became infected with COVID after being vaccinated, compared to 16 cases among those in the control group. The vaccinated kids had much milder symptoms.
Temporary side effects after vaccination among the younger children were less severe than adolescents and younger adults, Pfizer said. Children were much more likely to experience redness and swelling at the injection site, but less likely to experience fatigue, headache or joint pain.
Pfizer said its study was too small to detect any of the rare but serious adverse events like heart inflammation associated with vaccination. However, that condition occurs most often in teenage males between the ages of 16 and 19. It's less common in adolescents, and Pfizer said the rates will likely be even lower in young kids 5 to 11 years old.
Updated at 9:22 a.m.