The first results from the highly anticipated trial studying the effectiveness and safety of the Pfizer and BioNTech COVID-19 vaccine for children under 12 showed promising results.

The pharmaceutical companies said early results of their trials indicate the shots are safe for children and establish a strong antibody response against the virus.

Giving a two-dose regimen of 10 μg (micrograms) administered 21 days apart for children between the ages of five to 11-years-old was well tolerated, according to Pfizer and BioNTech. Side effects of the shots were also generally comparable to those of people between the ages of 16 to 25-years-old who received the vaccine.

This trial used a smaller vaccine dosage, 10 μg, than the regular 30 μg dose currently used for people 12-years-old and older. The dosage was selected as the preferred dose for safety and effectiveness in children.

News of the results come as pediatric cases of COVID-19 are increasing amid a nationwide surge of infections.

"Since July, pediatric cases of COVID-19 have risen by about 240 percent in the U.S. – underscoring the public health need for vaccination. These trial results provide a strong foundation for seeking authorization of our vaccine for children 5 to 11 years old, and we plan to submit them to the FDA and other regulators with urgency," said Albert Bourla, the chairman and CEO for Pfizer.

"Over the past nine months, hundreds of millions of people ages 12 and older from around the world have received our COVID-19 vaccine. 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," Bourla said in a statement.

Despite the strong results, it will be some time before the general public can see an official roll out of vaccines for children under the age of 12. Once the trials are completed, Pfizer and BioNTech will submit the results to the Food and Drug Administration for review and possible approval.

That is likely still several months away. Parents and caregivers will likely have to wait until the end of 2021 before a COVID-19 vaccine is fully approved for young children ages 5 to 11, Dr. Francis Collins, director of the National Institutes of Health, recently told NPR.

Trial results for children under 5 years of age could come later this year, the pharmaceutical companies said.

Pfizer and BioNtech are hoping to get the trial's data submitted to regulatory authorities soon.

"Already in March 2021, we have started the study to evaluate the immunization of younger children. Our objective was to generate and submit the data for school kids to regulatory authorities around the world before the winter season begins," Ugur Sahin, CEO and co-founder of BioNTech, said.

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