Alliance for Pandemic Preparedness

December 10, 2020

Safety and Efficacy of the BNT162b2 MRNA Covid-19 Vaccine



Keywords (Tags):

  • Results of the phase 3 double-blind, randomized, placebo-controlled trial for the BioNTech and Pfizer mRNA vaccine BNT162b2 (n=21,720 in vaccine group, and 21,728 in placebo group) showed a vaccine efficacy of 95% (95% CI 90.3-97.6), with 8 cases of COVID-19 (1 severe case) in the vaccine group and 162 cases (9 severe cases) in the placebo group. Efficacy was similar across subgroups defined by age, sex, race, ethnicity, body-mass index, and presence of co-existing conditions.
  • Reactogenicity events were common among vaccine recipients, including arm pain, fatigue and headache. Fever (temperature ≥38C) was reported after the second vaccine dose by 16% of participants <55 years old and 11% of participants >55. Few participants in either group had severe or serious adverse events, and the 6 deaths (2 in vaccine group, 4 in placebo group) were determined by investigators not to be related to the vaccine or placebo by investigators.
  • Participants were included from 152 sites in 6 countries (130 sites in the US). The majority were aged 18-55 (58%), white (83%), and male (51%). 35% were obese and 21% had at least one coexisting condition.

Polack et al. (Dec 10, 2020). Safety and Efficacy of the BNT162b2 MRNA Covid-19 Vaccine. New England Journal of Medicine.