Covid-19: Pfizer vaccine efficacy was 52% after first dose and 95% after second dose, paper shows
Elisabeth Mahase
Abstract
Covid-19: Pfizer vaccine efficacy was 52% after first dose and 95% after second dose, paper shows Elisabeth MahaseThe Pfizer and BioNTech covid-19 vaccine may provide some early protection, starting 12 days after the first dose, the peer reviewed results of a phase III trial have found.The study, published in the New England Journal of Medicine, 1 found that vaccine efficacy between the first and second doses was 52% (95% credible interval 29.5% to 68.4%), with 39 cases of covid-19 in the vaccine group and 82 cases in the placebo group.Seven or more days after the second dose, vaccine efficacy then rose to 95% (90.3% to 97.6%), with eight covid-19 cases reported in the vaccine group and 162 cases in the placebo group.
Topics & Concepts
Coronavirus disease 2019 (COVID-19)PlaceboMedicinePlacebo groupVaccine efficacySevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)2019-20 coronavirus outbreakVirologyInternal medicineVaccinationAlternative medicineOutbreakPathologyInfectious disease (medical specialty)DiseaseSARS-CoV-2 and COVID-19 ResearchVaccine Coverage and HesitancyCOVID-19 Clinical Research Studies