12-to-15-year-olds can now get Pfizer COVID-19 vaccine

The messenger RNA vaccine made by Pfizer and BioNTech is the first COVID-19 vaccine to be offered to people as young as 12 in the US after the Food and Drug Administration extended its emergency use authorization to include 12-to-15-year-olds.

People aged 12–17 are beginning to make up a greater proportion of COVID-19 cases, according to the US Centers for Disease Control and Prevention, and accounted for 9% of reported cases in April. There have been 127 deaths and over 13,000 hospitalizations related to COVID-19 in the age group since the pandemic started.

Pfizer tested its vaccine in a placebo-controlled trial of 2,260 adolescents aged 12–15 and found that it was 100% effective at preventing symptomatic COVID-19 starting 1 week after the second dose. The 12-to-15-year-olds also produced higher levels of neutralizing antibodies after their second shot compared with the 16-to-25-year-olds vaccinated in Pfizer’s earlier clinical trial.

Side effects such as pain at the injection site, fatigue, and headache were equally common in the 12–15 and 16–25 age groups. Lymphadenopathy, or swollen lymph nodes, lasting 1–10 days was more common in younger vaccine recipients, occurring in about 0.8% of 12-to-15-year-olds compared with about 0.4% of 16-to-55-year-olds–the comparison that Pfizer provided. There were no reports of anaphylaxis in the 12–15 group.

Based on the trial data, the FDA extended authorization of the vaccine to the 12-15 age group on May 10. Two days later, CDC’s Advisory Committee on Immunization Practices, a team of independent scientists that recommends how vaccines should be used, voted unanimously—with one abstention—in favor of using the vaccine.

Pfizer is also studying the vaccine in a trial of children aged 2–11, with results expected in September. Results from a trial in infants 6 months–2 years are expected before the end of the year.