The Food and Drug Administration authorized the emergency use of the Pfizer-BioNTech coronavirus vaccine for 12- to 15-year-old adolescents, the agency announced on Monday.

Why it matters: The move will allow millions more to access the vaccine as the nation seeks to achieve herd immunity.

• Pfizer has said its vaccine was 100% effective at protecting against COVID-19 in a trial of more than 2,200 children between the ages of 12 and 15.

What they're saying: “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. Parents and guardians can rest assured that the agency undertook a rigorous and thorough review of all available data," said Acting FDA Commissioner Janet Woodcock.

What's next: Moderna is expected to announce trial results for adolescents ages 12 to 17 in the second half of 2021, the New York Times reports.