Pfizer-BioNTech COVID-19 Vaccine Proven Effective in Young Children

On August 23, Pfizer announced updates to their Phase ⅔ clinical trial testing the efficacy of their COVID-19 vaccine in children six months through four years of age. The study found that three 3-µg dose series of the Pfizer-BioNTech COVID-19 vaccine demonstrated a 73% efficacy rate in participants. 

Related Article: Pfizer and BioNTech’s New Bivalent Omicron Vaccine Lined Up for Authorization from the FDA

Differences in the Vaccine Children Receive

Comirnaty is the name of the Pfizer-BioNTech COVID-19 vaccine. Currently, the United States Food and Drug administation (FDA) authorized Comirnaty for emergency use as a three-dose primary series for individuals six months through four years of age or as a two-dose primary series for individuals five years of age and older. The younger age group receives a third primary shot due to research showing that a third shot generates an antibody level comparable to young adults after receiving their two primary doses. 

In contrast, Moderna’s Spikevax vaccine only requires a two-dose primary series for those six months and older. Similar to the Pfizer-BioNTech COVID-19 vaccine, Spikevax received approval for emergency use.

Although Comirnaty initially received its Emergency Use Authorization (EUA) on August 23, 2021, the EUA only approved its use for individuals 16 years of age and older. It wasn’t until June 17 of this year that the vaccine received another EUA for individuals six months through four years of age. The basis for this approval was a Phase ⅔ clinical trial wherein children demonstrated an 80% vaccine efficacy rate and a safety profile consistent with the placebo. These findings from earlier this year form the basis for those announced today. 

Recent Clinical Trial Backs up Prior Findings

The study participants either received the dose series of the Pfizer-BioNTech COVID-19 vaccine or a placebo. Similar to the data gathered earlier this year, participants demonstrated a vaccine efficiency rate of 73.2%. In addition, the safety profile was still similar to the placebo. The only adverse effects observed were either mild or moderate. 

However, researchers identified some symptomatic cases of COVID-19 in the testing group. Testing the patient’s RNA revealed that the Omicron BA.2 strain was responsible for most of these cases. 

On the recent data, Albert Bourla, Chairman and Chief Executive Officer of Pfizer, said, “Building on the strong safety and immunogenicity data that led to FDA authorization of our COVID-19 vaccine for children six months through four years, we are pleased to share confirmatory evidence that a full course of vaccination helps protect against symptomatic disease, particularly during a time when the Omicron BA.2 strain was predominant.”

Pfizer and BioNTech plan to submit the updated efficacy data to global regulatory authorities like the FDA and the European Medicines Agency. They hope that the additional data will assist in gaining further approval for their vaccine’s administration to the tested age range in the countries that have yet to grant them such. 

Author

Max Heirich