For vaccination of youth ages 5 through 11 years:
The vaccine’s safety was studied in approximately 3,100 children ages 5 through 11 who received the vaccine and no serious side effects have been detected in the ongoing study.

  • The available safety data to support the EUA include more than 4,600 participants (3,100 vaccine, 1,538 placebo) ages 5 through 11 years enrolled in the ongoing study. In this trial, a total of 1,444 vaccine recipients were followed for safety for at least 2 months after the second dose.

Side effects were generally mild to moderate in severity and occurred within two days after vaccination, and most went away within one to two days.

For vaccination of youth ages 12 through 15 years:

There were a smaller number of participants in this trial than in trials for adults, but thousands of adolescents received the COVID-19 vaccines during clinical trials and tens of millions of adults in the United States have received COVID-19 vaccines under the most intense safety monitoring in U.S. history.

It is important to note that although the trial enrolled a relatively narrow range of ages (12-15 years and 16-25 years), there were 1,131 participants aged 12-15 years who received the Pfizer BioNTech vaccine and there were 1,867 participants aged 16-25 years that received the vaccine. The earlier published clinical trial supporting EUA for 16 years and above was larger (18, 860 vaccine recipients) it was also across a much broader age range (16-89 years).

The good news is that through the trial it was noted that adolescents showed similar side effect patterns to adults and that those aged 12-15 years had immune responses that were higher as compared to those aged 16-25 years, and the vaccine efficacy estimate was 100% for symptomatic lab-confirmed COVID-19.