Pfizer is applying to EU regulators to have its vaccine approved for use in children aged 12 to 15, a move that could help European countries to achieve herd immunity.
The US company and its German partner BioNTech say their submission to the European Medicines Agency is based on a study of 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 two years.
German Health Minister Jens Spahn welcomed the news that the vaccine might soon be used in older children.
“This can make a further real difference to our vaccine campaign, if approval is granted,” he said on a visit to a vaccine manufacturing plant in the German town of Reinbek.
Ugur Sahin, co-founder and chief executive of BioNTech, said the shot could become available for those age groups from June if EU approval is granted.
Pfizer is also asking to US regulators to extend the vaccine’s authorisation to children.
Most Covid-19 vaccines being distributed worldwide are for adults, who are at higher risk from the coronavirus.
But vaccinating people of all ages will be critical to stopping the pandemic, especially since research shows older children in particular may play a role in spreading the virus.
Immunising children against Covid-19 might also give authorities more confidence to reopen schools.
Other Covid-19 vaccine manufacturers including AstraZeneca, Moderna and Johnson & Johnson are studying whether their drugs can be used safely in children.
The Pfizer vaccine was the first one given the green light by EU regulators last December, when it was approved for people aged 16 and over.
EU nations made a slow start to the vaccination campaign, frustrating efforts to reach herd immunity.
But countries including Germany and France are now picking up the pace. Germany set a new European record on Wednesday with more than a million doses handed out in a day.
“That shows how much speed we’ve gained,” Mr Spahn said.
In France, President Emmanuel Macron said that all adults would be eligible for vaccines from June 15.
France's vaccination programme has now reached 99 per cent of care home residents and 69 per cent of over-70s, according to figures cited by Mr Macron.
The bloc is seeking to buy another 1.8 billion vaccine doses from Pfizer and BioNtech by 2023, some of which are intended for use in children.