NHK has learned that Japan's health ministry is considering limiting the use of Pfizer's coronavirus vaccine to people aged 16 or older for the time being.
Last month, Pfizer sought approval in Japan for its vaccine, jointly developed with German partner BioNTech. It's the only supplier that has applied for authorization in the country.
Sources say the health ministry is considering excluding under-16s because the vaccine's ongoing clinical trial in Japan involves only adults aged 20 or older.
They say the results of trials conducted abroad also lack sufficient data on children 15 or younger. The lower risk of children developing severe symptoms from the virus is said to be another factor.
The United States and Britain have already rolled out the Pfizer vaccine. They, too, limit its use to people 16 or older.
Japan's heath ministry will finalize the target-age based on data from the domestic clinical trial. It plans to swiftly study the vaccine's safety and efficacy, and hopes to start inoculating healthcare workers in late February.
Japan has an agreement with Pfizer to obtain enough doses of the vaccine for 60 million people in the first half of this year.