The first participants have been dosed in a global Phase 2/3 study to further evaluate the Pfizer-BioNTech COVID-19 vaccine in healthy pregnant women 18 years of age and older.
The trial is designed as a randomised, placebo-controlled, observer-blind study in approximately 4,000 healthy pregnant women 18 years of age or older vaccinated during 24 to 34 weeks of gestation.
The study will evaluate the safety, tolerability, and immunogenicity of two doses of BNT162b2 or placebo administered 21 days apart.
Each woman will participate in the study for approximately 7 to 10 months, depending on whether she was randomized to receive the vaccine or placebo.
The study will assess safety in infants of vaccinated pregnant women and the transfer of potentially protective antibody to their infants. Infants will be monitored through approximately six months of age.
As established in the study protocol, after a participant’s infant is born, maternal trial participants will be unblinded and those who were in the placebo group will receive the vaccine.
Prior to conducting their COVID-19 vaccine clinical trial in pregnant women, Pfizer and BioNTech completed a developmental and reproductive toxicity (DART) study with BNT162b2, which was required by the regulatory authorities before starting the study in pregnant women. Those studies showed no evidence of fertility or reproductive toxicity in animals.
Pfizer and BioNTech expect to start additional studies in children between the ages of 5 and 11 over the next couple of months, and in children younger than 5 later in 2021.
Safety and efficacy in subjects 12 to 15 years of age are already being evaluated in the global Phase 3 study (C4591001) and the relevant data are planned to be submitted to the regulatory authorities in the second quarter of 2021.