Pfizer-BioNTech Reports 100% Efficacy in Adolescents Given COVID-19 Vaccine

March 31, 2021
Kevin Kunzmann

The pivotal phase 3 data, based off 18 reported cases among placebo patients, includes the companies' intention to request authorization for adolescents aged 12-15 years old.

Pfizer-BioNTech has reported topline results of a pivotal phase 3 trial showing 100% vaccine efficacy with BNT162b2 in the prevention of COVID-19 among adolescents aged 12-15 years old.

In the first iteration of shared pediatric data for an mRNA vaccine in the prevention of COVID-19, the companies also announced their intention to submit such data to the US Food and Drug Administration (FDA) for an amendment to their Emergency Use Authorization (EUA) of BNT162b2 to include use in adolescents.

The Adolescent Trial

The phase 3 US-based trial included 2260 adolescents aged 12-15 years old, administered either two-dose vaccine (n = 1131) or placebo (n = 1129) for the prevention of COVID-19.

On Wednesday morning, Pfizer announced that 18 cases of COVID-19 were confirmed among participants administered placebo, versus none among those administered BNT162b2.

What’s more, investigators observed a strong immunogenicity from the vaccine in fully-dosed participants: 1239.5 SARS-CoV-2 neutralizing antibody geometric mean titers (GMTs) 1 month following the second dose of BNT162b2. Comparatively, participants aged 16-25 years old reported GMT of 705.1 at that time point in adult-based analyses.

Younger participants administered the vaccine reported good tolerance, with side effects consistent with those observed in participants aged 16-25 years old.

The companies now intend to submit their pivotal data for publication by a scientific peer-reviewed journal.

The Pediatric Trial

Pfizer-BioNTech additionally shared an update on the phase 1/2/3 study observing the safety, tolerability, and immunogenicity of BNT162b2 in children aged 6 months to 11 years old.

The pediatric population is stratified into children aged 5-11 years, 2-5 years, and 6 months to 2 years. Dosing for the oldest population began just last week, and the companies intend to begin dosing the 2-5 year-old population next week.

What’s Next

On the basis of the new data, the companies are submitting the supplemental adolescent data to the FDA, as well as the European Medicines Agency (EMA), “as soon as possible” in order to secure emergency authorization expansions.

The timing of the submission aligns with the greater interests of the general school system schedule, as well as burgeoning concern of increased cases and SARS-CoV-2 variant presence in the US.

“We share the urgency to expand the authorization of our vaccine to use in younger populations and are encouraged by the clinical trial data from adolescents between the ages of 12 and 15,” Albert Bourla, chairman and chief executive officer of Pfizer, said in a statement. “We plan to submit these data to FDA as a proposed amendment to our Emergency Use Authorization in the coming weeks and to other regulators around the world, with the hope of starting to vaccinate this age group before the start of the next school year.”

Ugur Sahin, chief executive offcer and co-founder of BioNTech emphasized the value of the mRNA vaccine’s real-world efficacy and contribution toward the global pursuit of “normalcy” in the aftermath of the pandemic. Children are not excluded from that pursuit, he said.

“The initial results we have seen in the adolescent studies suggest that children are particularly well protected by vaccination, which is very encouraging given the trends we have seen in recent weeks regarding the spread of the B.1.1.7 UK variant,” Sahin said. “It is very important to enable them to get back to everyday school life and to meet friends and family while protecting them and their loved ones.”