Moderna on Thursday filed for emergency use authorization from the Food and Drug Administration to use its Covid-19 vaccine in adolescents ages 12 to 17.

If cleared by the FDA, it will become the second Covid-19 vaccine available in the United States for teens under 18 along with Pfizer-BioNTech’s vaccine, which was authorized for adolescents ages 12 to 15 in May.

Moderna said in May that results from its clinical trial among children ages 12 to 17 showed its two-dose mRNA vaccine to be safe and highly effective. The trial included more than 3,700 participants.

Side effects were generally mild or moderate, the company said. Arm pain at the injection site was the most common side effect after the first dose and headache, fatigue, muscle aches and chills were most common after the second dose.

(AP)