New top story from Time: Pfizer-BioNTech’s COVID-19 Vaccine Works for Teens, According to a New Study

Pfizer-BioNTech says their COVID-19 vaccine is 100% efficacious in protecting adolescents aged 12 to 15 years from COVID-19 disease.

On March 31, the companies released a statement summarizing the results of their study of the safety and efficacy of their vaccine, which is already authorized in the U.S. and elsewhere for use in adults 16 years or older, in this younger age group. The results have been highly anticipated as state and local leaders—not to mention parents—are to keen send teens back to in-person school; this study suggests a path towards a return to pre-pandemic learning conditions, in which students won’t spread COVID-19 in the classroom.

The trial involved 2,260 adolescents 12 to 15 years old, who were randomly assigned to get two doses of the COVID-19 vaccine or two doses of placebo. During the study, which began earlier this year, 18 teens developed COVID-19, all of them in the placebo group. The researchers found that the levels of virus-fighting antibodies generated by those getting the vaccine were considerably higher than levels among those receiving the placebo.

“We share the urgency to expand use of our vaccine to additional populations and are encouraged by the clinical trial data from adolescents between the ages of 12 and 15,” Pfizer CEO Albert Bourla said in the statement. Based on the new data, the companies plan to ask the U.S. Food and Drug Administration (FDA) to expand emergency use authorization for the vaccine to include 12- to 15-year-olds.

Even more encouraging the antibody levels exceeded the levels of those in the 16-25 year old age group in the original adult trial of the shots. And the researchers found no significant side effects from the vaccine among the teens, although they will continue to monitor them for long term efficacy of the shot as well as side effects for two years.

Those data will ultimately help to enhance understanding of how COVID-19 affects children. So far, experts say children don’t seem to be affected by the virus as severely as older adults, although protecting them from symptoms of the disease is critical, not least as an additional way to curb spread of the virus. In a recent study of adults published by the U.S. Centers for Disease Control, scientists found that the mRNA-based vaccine not only protects against symptoms of the disease, but can ward off infection with the virus in the first place. The adolescent study wasn’t designed to confirm this in the younger population as well, but given younger people’s more responsive immune systems, it’s likely they might benefit from the same protection from infection. That would mean vaccinated students are far less likely to spread the virus in a school setting because they’re less likely to get infected to begin with.