Pfizer (PFE) and BioNTech (BNTX) announced Monday that their COVID-19 vaccine is now safe for children aged 5 to 11 following a clinical trial and will be submitted for Food and Drug authorization as soon as possible.

The drugmakers said the vaccine was tested among 2,268 children, using a two-shot regimen of 10 microgram doses 21 days apart – a third of the dose that was administered to ages 12 and older.

Pfizer said the 10 mg dose was “carefully selected as the preferred dose for safety, tolerability, and immunogenicity.”

The companies said the shot provided a “robust” response and was well tolerated with side effects that were similar to those seen in studies of individuals aged 16 to 25.

According to the Centers for Disease Control and Prevention, common side effects from the COVID shot include fatigue, headaches, muscle pain, chills, fever, and nausea.

“We are eager to extend the protection afforded by the vaccine to this younger population, subject to regulatory authorization, especially as we track the spread of the Delta variant and the substantial threat it poses to children,” Pfizer CEO Albert Bourla said in a statement.

The Pfizer-BioNTech COVID vaccine has been approved by the FDA for administration in those 12 and older. The Moderna and Johnson & Johnson vaccine is only authorized for adults 18 and older.

The Pfizer booster shot was also recommended for ages 65 and older on Friday. Immunocompromised adults are also eligible for a booster shot from Pfizer or Moderna.

The companies also said that they expect to release clinical trial data on its COVID vaccine on children as young as six months to 5 years of age by the fourth quarter of this year.

Over 220 million doses of the Pfizer-BioNTech COVID vaccine have been administered, according to the CDC.

As of Monday premarket hours, shares of Pfizer were trading at $43.24, down 65 cents, or 1.48%, while shares of BioNTech were trading at $341.31, down $17.87, or 4.98% at the same time. 

The United States says it will ship half a billion dozes of the Pfizer vaccine to poor countries starting late this month The United States says it will ship half a billion dozes of the Pfizer vaccine to poor countries starting late this month Photo: AFP / JUSTIN TALLIS