Pfizer/BioNTech Vaccine Trial In Young Kids Marked By High Level Of Unblinding

04 Jul 2022

The unblinding process began months before a third dose was added to the study in the 6 months-4 years group. Consequently, only about one-third of vaccine recipients in each age cohort received three doses of BNT162b2.

Car blind — Pfizer/BioNTech began lowering the blind for trial participants four months before adding a third dose. • Source: Shutterstock

Pfizer Inc./BioNTech SE’s COVID-19 vaccine trial in very young children involved extensive unblinding that resulted largely from a late-study pivot from two to three doses and participants who aged out of the cohort during the extended study.

Because of the unblinding, only about one-third of subjects originally randomized to the vaccine group received all three doses.