Moderna says its COVID-19 vaccine appears safe, 96% effective in teens 12-17

Moderna announced on Thursday that data from an ongoing trial of its COVID-19 vaccine for teens ages 12-17 was 96% effective against the novel coronavirus. 

No additional side effects or serious safety concerns were reported so far, according to the company. 

The trial consists of 3,235 teenagers, and efficacy for the vaccine was approximately 96% for the participants who received at least one injection, Moderna reported. The company also said that because incidence rate of COVID-19 is lower in adolescents and teenagers, the vaccine’s effectiveness on the trial patients is mainly against milder symptoms of the disease. 

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The company said the majority of adverse effects of the teen vaccine were mild or moderate in severity. The most common adverse effect was pain at the injection site. 

Moderna said a trial for a vaccine with participants aged 6 months to 11 years is still ongoing and data will hopefully be released soon. 

Recently, the company announced that another ongoing trial for its COVID-19 vaccine booster was found to be effective against concerning coronavirus variants, including the B.1.351 variants first identified in South Africa and the P.1 variant first identified in Brazil.

Moderna said a single dose of its vaccine given as a booster to previously fully vaccinated individuals "increased neutralizing antibody" responses against both variants.

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Meanwhile, in Canada, health officials approved Pfizer’s COVID-19 vaccine Wednesday for children as young as 12.

Dr. Supriya Sharma, chief medical adviser at Health Canada, confirmed the decision for ages 12 to 15 and said it will help children return to a normal life. Canada is the first country to authorize Pfizer for that age group. The U.S. and the European Union are also reviewing it.

The vaccine was previously authorized for anyone 16 or older.

The U.S. Food and Drug Administration is also expected to authorize Pfizer’s vaccine for young people by next week, setting up shots for many before the beginning of the next school year. The announcement comes barely a month after the company found that its shot, which is already authorized for those age 16 and older, also provided protection for the younger group.

Pfizer in late March released preliminary results from a vaccine study of 2,260 U.S. volunteers ages 12 to 15 showing there were no cases of COVID-19 among fully vaccinated adolescents compared with 18 among those given dummy shots.

The Associated Press contributed to this story.