What is the BNT-162b2 coronavirus disease 2019 (COVID-19) vaccine?

Updated: Feb 28, 2021
  • Author: David J Cennimo, MD, FAAP, FACP, AAHIVS; more...
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  • Genetic-code vaccine
  • Storage and shipping requirements: Frozen; ultra-cold storage of -70ºC
  • Requires reconstitution
  • Once thawed, stable refrigerated for up to 5 days
  • Room temperature stability: 2 hours
  • Dose: 2 injections 21 days apart

BNT-152b2 (Pfizer) is a nucleoside-modified messenger RNA (modRNA) vaccine (BioNTech and Pfizer) that encodes an optimized SARS-CoV-2 receptor-binding domain (RBD) antigen.

The ongoing multinational phase 3 trial included 43,548 participants 16 years and older who were randomly assigned to receive vaccine or placebo by injection; 43,448 participants received vaccine or placebo (vaccine group, 21,720; placebo group, 21,728). Approximately 42% of global participants and 30% of US participants were of racially and ethnically diverse backgrounds, and 41% of global and 45% of US participants were 56-85 years of age.

Vaccine efficacy was 95%, and no serious safety concerns were observed. The only grade 3 adverse event with a frequency of greater than 2% was fatigue at 3.8%; headache occurred in 2% of participants. Short-term mild-to-moderate pain at the injection site was the most commonly reported reaction, and severe pain occurred in less than 1% of participants across all age groups. [9]

Results from an observational study of real world data from healthcare workers (HCWs) employed in a large medical center in Israel after their first vaccine dose has been published. Among 9109 eligible staff, 7214 (79%) had received a first dose and 6037 (66%) had received the second dose between December 19, 2020 and January 24, 2021. Compared with a symptomatic COVID-19 rate of 5 per 10,000 person-days in unvaccinated HCWs, disease rates were 2.8 and 1.2 per 10,000 person-days on days 1-14 and days 15-28 after the first vaccine dose, respectively. Adjusted rate reductions of COVID-19 disease were 47% (95% CI 17-66) and 85% (71-92) for days 1-14 and days 15-28 after the first dose, respectively. [15]  

In another observational study, integrated data repositories in Israel’s largest health care organization were used to evaluate mass immunization effectiveness. The 5 outcomes evaluated included documented SARS-CoV-2 infection, symptomatic Covid-19, hospitalization, severe illness, and death. The observations suggest the vaccine is effective for a wide range of COVID-19–related related outcomes that are consistent [16] with the randomized trial by Polack et al. [9]

In February 2021, a proposed EUA update was submitted to the FDA that demonstrated short-term storage at temperatures more commonly found in typical pharmaceutical freezers. If approved, this new storage option could offer greater flexibility in managing and maintaining vaccine distribution and supply. 

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