|Articles|October 22, 2021

Pfizer-BioNTech COVID-19 Vaccine over 90% Effective in Children 5-11

Author(s)Nina Cosdon

Data presented to the Vaccines and Related Biological Products Advisory Committee (VRBPAC) showed 2 10 µg doses of the Pfizer-BioNTech vaccine to be 90.7% effective in children older than 5 and younger than 12.

This morning, the Food and Drug Administration released trial data showing children 5 to <12 years of age were 90.7% protected from symptomatic COVID-19 after receiving 2 doses of the Pfizer-BioNTech vaccine.

Children were given 2 10 µg doses of the Pfizer-BioNTech (BNT162b2) vaccine 3 weeks apart. The trial population was comprised of approximately 1500 children between 5 and <12 years of age. According to the Vaccines and Related Biological Products Advisory Committee (VRBPAC) briefing document, “The results demonstrated that the two-dose primary series of BNT162b2 10 µg given to children 5 to <12 years of age elicited SARS-CoV-2 50% neutralizing titers that were non-inferior to the titers elicited by two doses of BNT162b2 30 µg in young adults 16 to 25 years of age.”

Supplemental analysis conducted to gauge efficacy against the Delta variant found that serum neutralizing titers 1 month after the second dose were comparable to those against the original strain.

Vaccine efficacy (VE) against laboratory-confirmed symptomatic COVID-19 disease began at least 7 days after the second dose. In participants without prior COVID-19 infection, VE was 90.7% (% (2-sided 95% confidence interval [CI]: 67.7%, 98.3%). There were no cases of severe COVID-19 and no cases of MIS-C reported as of the 3-month follow-up period after the second vaccine.

The reactogenicity profile of this age group was mild to moderate; most events arose 1-2 days after vaccination and dissipated soon after. The most common side effects were injection site pain, fatigue, headache, muscle pain, and chills. The adverse event (AE) profile post-vaccination mostly reflected reactogenicity. No serious AEs related to the vaccine were reported. Additionally, no cases of myocarditis or pericarditis were observed from the vaccination period through the 3 months of follow-up after the second dose.

VRBPAC is scheduled to meet on Tuesday to discuss this trial and other data included in the BNT162B2 briefing document.


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