On Monday (May 10), the U.S. Food and Drug Administration (FDA) extended emergency approval for the Pfizer-BioNTech COVID-19 vaccine to include adolescents between the ages of 12 and 15 years old.
The original emergency approval, issued on Dec. 11, 2020, allowed Pfizer's vaccine to be given to those who were 16 years of age or older.
"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," Dr. Janet Woodcock, acting FDA Commissioner, said in a statement. "Parents and guardians can rest assured that the agency undertook a rigorous and thorough review of all available data, as we have with all of our COVID-19 vaccine emergency use authorizations."
Related: Quick guide: COVID-19 vaccines in use and how they work
The FDA ruled that the "known and potential benefits" of the vaccine in this age group outweigh the "known and potential risks," according to the statement. On March 31, Pfizer and BioNTech announced that the vaccine was 100% effective in preventing COVID-19 in children between the ages of 12 and 15 based on results from a phase 3 trial, Live Science previously reported. In the trial, there were zero COVID-19 cases among those who were given the vaccine and 18 COVID-19 cases among those given the placebo.
The trial involved 2,260 participants in that age group; half received the vaccine and half received a placebo. The side effects in this age group "were consistent" with those reported in the older age groups; the most common side effects were pain at the injection site, tiredness, headache, chills, muscle pain, fever and joint pain, according to the statement.
The Pfizer vaccine will be given to adolescents as two doses three weeks apart, the same administration and dosing as approved for the older age groups. Between March 1 and April 30, about 1.5 million COVID-19 cases were reported among adolescents between the ages of 11 and 17, according to the statement.
This emergency approval extension means that another 5% of the U.S. population — nearly 17 million people — is eligible to receive a COVID-19 vaccine, according to CNN. That means that 85% of the U.S. population is now eligible.
Originally published on Live Science.