Pfizer Inc. and BioNTech SE announced on Wednesday, May 6, 2020, that the first participants have been dosed in the U.S in the Phase 1/2 clinical trial for the BNT162 vaccine program to prevent COVID-19. The trial is part of a global development program, and the dosing of the first cohort in Germany was completed last week. The Phase 1/2 study is designed to determine the safety, immunogenicity and optimal dose level of four mRNA vaccine candidates evaluated in a single, continuous study. The dose level escalation portion (Stage 1) of the Phase 1/2 trial in the U.S will enrol up to 360 healthy subjects into two age cohorts (18-55 and 65-85 years of age). The first subjects immunized in Stage 1 of the study will be healthy adults 18-55 years of age. Older adults will only be immunized with ...