By Kim Mackrael and Jared S. Hopkins

OTTAWA -- Canada authorized the use of the Pfizer-BioNTech Covid-19 vaccine for adolescents, moving ahead of the U.S. Food and Drug Administration and marking the first time a Covid-19 vaccine will be available for children in North America.

Health Canada said its authorization means children between the ages of 12 and 15 will be able to receive the Pfizer-BioNTech vaccine. It didn't provide a timeline for when the two-dose shot would become available to that age group.

The Covid-19 vaccine developed by Pfizer Inc. and BioNTech SE was found to be 100% effective in protecting against symptomatic disease in a study of more than 2,200 children, the companies said in late March. Researchers didn't find any safety concerns.

Canadian officials said they reviewed the study's results in making their decision. "After completing a thorough and independent scientific review of the evidence, the department determined the vaccine is safe and effective when used in this younger age group," said Dr. Supriya Sharma, senior medical adviser at Health Canada.

The FDA is considering a request for authorization of the Pfizer-BioNTech vaccine for adolescents, which could make the vaccine available to children in the coming weeks. Regulators in Europe are also reviewing a request to authorize the vaccine for children.

Pfizer said Tuesday that it plans to ask U.S. regulators to authorize the vaccine for children between 2 and 11 years old in September, should a study under way prove positive.

Children are at lower risk of Covid-19 infection than adults, according to health experts, and when they are infected they tend to experience milder symptoms. Yet some can become seriously ill and some can spread the virus.

The vaccine's expanded use is expected to boost Canada and the world's vaccination campaign seeking to immunize as many people as possible before dangerous variants able to elude shots emerge.

Canada has experienced a damaging third wave of infections in recent months after a slow start to its vaccination campaign, prompting some jurisdictions to close schools, restaurants and nonessential stores. Canada's per capita rate of reported Covid-19 cases surpassed that of the U.S. for the first time last month, but cases in Canada have leveled off in recent weeks.

"Today's expansion of our authorization represents a significant step forward in helping the Canadian government broaden its vaccination program and begin to help protect adolescents before the start of the next school year," said Fabien Paquette, head of vaccines for Pfizer's Canadian subsidiary.

Write to Kim Mackrael at kim.mackrael@wsj.com and Jared S. Hopkins at jared.hopkins@wsj.com

(END) Dow Jones Newswires

05-05-21 1219ET