On Friday, Pfizer announced it was going to modify it clinical trial for coronavirus vaccines for young children to include a third shot. This development will delay the roll out of vaccines for children under five years old.
Pfizer made the decision to add the third dose for all children and babies ages 6 months to 5 years after initial data revealed a two-dose regimen did not provide the expected immunity in younger children. The modified trial will include evaluating a third dose of the vaccine at least two months after the second dose of the two-dose series. In a statement, Pfizer said, “If the three-dose study is successful, Pfizer and BioNTech expect to submit data to regulators to support an Emergency Use Authorization (EUA) for children 6 months to under 5 years of age in the first half of 2022."