Frenck RW, Klein NW, Kitchin N, et al. - As children and adolescents can suffer severe Covid-19 illness, especially those with underlying medical conditions, and an important role is played by these individuals in SARS-CoV-2 transmission, they suggest the necessity for a safe, effective vaccines to protect this population, facilitate in-person learning and socialization, and contribute to herd immunity. In an ongoing multinational, placebo-controlled, observer-blinded trial, participants were randomly assigned in a 1:1 ratio to receive two injections, 21 days apart, of 30 μg of BNT162b2 or placebo. A total of 2,260 adolescents 12 to 15 years of age were administered injections; 1,131 were provided BNT162b2, and 1,129 were provided placebo. The BNT162b2 vaccine had a favorable safety profile in 12-to-15-year-old recipients. It resulted in a greater immune response among these adolescents relative to young adults, and was highly effective against Covid-19.