An advisory panel of experts to the U.S. drug regulator will meet in June to review requests from Pfizer Inc and Moderna Inc for use of their COVID-19 vaccines in young children, the U.S. Food and Drug Administration said on Friday.

The FDA said it would also convene a meeting to review Novavax's request for emergency use authorization of its vaccine in individuals aged 18 and older.

On Thursday, Moderna sought authorization from the FDA for its vaccine for children under the age of 6. Pfizer's primary vaccine is authorized for children aged 5 and older in the United States.

The submission for children aged 6 months to under 6 years will be completed next week, Moderna said.

Pfizer, which previously said it expected its latest vaccine data for children under the age of 5 in April, did not give a timeline for when it plans to release that data. However, the company said it would complete its submission to regulators for authorization in the age group by June.

It is not clear how many parents will want to vaccinate their children in the under-5 age group in the U.S. as COVID-19 is often more mild in children than adults.

Only 28% of children in the 5-to-11 age group are fully vaccinated in the United States, according to the U.S. Centers for Disease Control and Prevention.

The Vaccines and Related Biological Products Advisory Committee (VRBPAC) is expected to meet on June 7 to discuss Novavax's application, and will convene on June 8, 21, and 22 to discuss Pfizer and Moderna's data, the FDA said.

The U.S. regulator also plans to convene a meeting to discuss whether the SARS-CoV-2 strain composition of COVID-19 vaccines should be modified, and if so, which strain(s) should be selected for the fall of 2022.