Pfizer and BioNTech have submitted a request for European Union drug regulators to extend the approval of the companies' Coronavirus vaccine to include children ages 12 to 15, a move that could offer younger and less at-risk populations in Europe access to the shots for the first time.

In a statement on Friday, the two companies said their submission to the European Medicines Agency was based on an advanced study in more than 2,000 adolescents that showed the vaccine to be safe and effective.

The children will continue to be monitored for longer-term protection and safety for another two years.

BioNTech and Pfizer previously had requested their emergency use authorisation with the US Food and Drug Administration also be extended to children 12-15.

The COVID-19 vaccine made by Pfizer and BioNTech was the first one to be granted a greenlight by the EMA in December, when it was licensed for anyone age 16 and over across the 27-nation EU.