Pfizer-BioNTech COVID-19 Vaccine Found 100% Effective in Younger Teens

Pfizer-BioNTech announced today the complete protection against infection with SARS-CoV-2 among youth aged 12 to 15 years.

In participants aged 12 to 15 years, the Pfizer-BioNTech vaccine BNT162b2 demonstrated 100% efficacy and strong antibody responses, according to a company announcement released Wednesday, March 31, 2021.

The company reported the vaccine was well tolerated and that the response seen in this trial exceeds that found in an earlier trial of the vaccine with participants aged 16 to 25 years.

The companies plan to submit the data to regulatory bodies in the US and European Union for expansion of current emergency and conditional use authorizations, respectively.

Pfizer CEO Albert Bourla said in the company statement that the companies hope vaccination for adolescents might begin before the opening of the next school year.

The phase 3 trial enrolled 2,260 adolescents aged 12 to 15 years who were randomized to receive 2 doses of the vaccine (n=1,129) or placebo (n=1131). One month after the second dose, adolescents vaccinated with BNT162b2 demonstrated SARS-CoV-2–neutralizing antibody geometric mean titers (GMTs) of 1,239.5, indicating a strong immunogenic response. This result was noninferior to GMTs generated in participants aged 16 to 25 years (705.1 GMTs) in the earlier Pfizer analysis. Tolerability was similar across the trials with side effects generally consistent between the 2 age groups.

Pfizer and BioNTech announced last week that they had begun studies in children as young as six months (range 6 months to 11 years), which will test whether lower doses should be used.

The Pfizer-BioNTech vaccine was the first to receive US FDA Emergency Use Authorization (EUA), in December 2020. The EUA was granted based on a global phase 3 clinical trial that demonstrated efficacy of 95%.


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