Pfizer's COVID vaccine remains 100% effective in kids after four months
New follow-up data from Pfizer’s Phase 3 trial testing its mRNA COVID-19 vaccine in 12 to 15 year olds show robust efficacy up to four months after the two-dose protocol. The data reveals the vaccine is 100 percent effective at preventing symptomatic SARS-CoV-2 infection.
“As the global health community works to increase the number of vaccinated people around the world, these additional data provide further confidence in our vaccine’s safety and effectiveness profile in adolescents,” says Pfizer CEO Albert Bourla. “This is especially important as we see rates of COVID-19 climbing in this age group in some regions, while vaccine uptake has slowed.”
The new data, yet to peer-reviewed and published, offer insight into the safety and efficacy of the Pfizer vaccine up to six months beyond the second dose. The Phase 3 trial enrolled 2,226 participants aged between 12 and 15 years.
The results show 30 confirmed cases of COVID-19 in the placebo group and zero cases in the vaccine group, across a follow-up period of four months. This translates to 100 percent efficacy at preventing symptomatic COVID-19. And no serious adverse safety events were detected across a follow-up of at least six months.
“These are the first and only disclosed longer-term data demonstrating the safety and efficacy of a COVID-19 vaccine in individuals 12 through 15 years of age,” explains Ugur Sahin, CEO of BioNTech, the company working with Pfizer on the vaccine. “The growing body of data we have compiled from clinical trials and real-world surveillance to date strengthen the base of evidence supporting the strong efficacy and favorable safety profile of our COVID-19 vaccine across adolescent and adult populations.”
The new Pfizer announcement makes no reference to concerns over the heart inflammation side effect, known as myocarditis, seen in a small number of young people following mRNA vaccination. It is likely this particular Phase 3 trial is not big enough to detect this rare side effect.
However, recent analysis of real-world vaccination data from the Centers for Disease Control and Prevention (CDC) found around six in every 100,000 males aged between 12 and 17 reported mild myocarditis following mRNA vaccination.
The CDC analysis indicates these cases of myocarditis are mostly mild and resolve quickly. Plus, the CDC points out, this side effect is so rare that adolescents are still more likely to suffer severe COVID-19 and hospitalization than experience myocarditis from vaccination.
Pfizer plans to submit this data to the FDA as part of its submission for full approval of the vaccine in this age group. In May the FDA issued emergency use authorization to Pfizer for its vaccine in 12 to 15 year olds and in August the vaccine received full market approval for everyone over the age of 16.
A number of countries around the world have been safely administering Pfizer’s COVID-19 vaccine to 12 to 15 year olds for many months now, including Canada, Singapore and several European countries.