Pfizer and BioNTech say vaccine prevents Covid-19 in adolescents

Pfizer and BioNTech said Wednesday that their Covid-19 vaccine prevented symptomatic disease and was well-tolerated in a Phase 3 study of adolescents ages 12 to 15.

The companies say they will submit the data to the Food and Drug Administration as an amendment to the vaccine’s emergency use authorization, and will also submit the results to other regulators around the world.

Pfizer CEO Albert Bourla said in a press release that the companies hope it will be possible to begin vaccinating adolescents in this group before the beginning of the next school year.

The Phase 3 trial enrolled 2,260 adolescents who were randomly assigned to receive two doses of the vaccine or placebo. The main measure of the vaccine’s efficacy was whether a subset of subjects developed antibodies at the same level seen in older adolescents and adults. The antibody levels, expressed as SARS-CoV-2 neutralizing geometric mean titers, were 1,239.5, compared to geometric mean titers of 705.1 in subjects between the ages of 16 and 25 in previous studies. Those levels are considered non-inferior to one another.

Natalie Dean, a statistician specializing in vaccines at the University of Florida, said that the data on cases of Covid-19 is encouraging. “Considering that wasn’t even the primary aim, that’s a good amount of data because it’s coupled with the other information.”

The companies also said that the vaccine was well-tolerated, with symptoms similar in the 12 year-old to 15 year-old age group as among those aged 16 to 25. The vaccine is authorized in the U.S. for people aged 16 and older.