TAMPA (WFLA) – Pfizer has received approval from the FDA to expand the emergency use of its COVID-19 vaccine to children ages 12-15.

The Pfizer vaccine was the first COVID-19 vaccine to be granted emergency use authorization in the United States.

Pfizer and BioNTech asked the FDA for full approval of their COVID-19 vaccine on Friday. If the FDA grants the request from Pfizer and its German partner BioNTech, it would be the first vaccine to get full approval.

NBC News reports the FDA will likely take several weeks to review the application from Pfizer and BioNTech.

The move will open up vaccines to millions of Americans and hopefully edge the country closer to reaching herd immunity.

In March, Pfizer said its clinical trials revealed its vaccine to be 100-percent effective for kids ages 12 to 15.

Kids had side effects similar to young adults, the company said. The main side effects are pain, fever, chills and fatigue, particularly after the second dose.

“We share the urgency to expand the use of our vaccine,” Pfizer CEO Albert Bourla said in a statement. At the time, he expressed “the hope of starting to vaccinate this age group before the start of the next school year” in the United States.