Pfizer said that a third shot of its COVID-19 vaccine boosted immunity against the Omicron variant in children between the ages of five and 11. The company released the results of a clinical trial that found the booster shot increased antibody levels sixfold, while a sub-analysis showed that 30 participants in the study had a 36-fold increase in their antibody levels.
The booster shot, which was given six months after the initial two-dose series was complete, is the same smaller 10 microgram dose that is authorized for kids. A full 30 microgram dose is authorized for anybody over the age of 12.
Pfizer said that it plans to ask the Food and Drug Administration for an emergency use authorization for the booster shot in adolescents.
While the vaccine provided strong protection against earlier strains of COVID-19, the Omicron variant drastically reduced the efficacy in children, which dropped from 68% to 12% against infection. However, the vaccine still provides strong protection against severe illness and hospitalization.
The pharmaceutical company is also working on a vaccine for children under five. Currently, the vaccine has not been shown to provide a strong immune response in children between two and four years old. The company said it is testing a third dose of its vaccine in toddlers, hoping that it will provide protection against COVID-19.