Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Meta-Analysis
. 2021 Aug;29(4):1075-1090.
doi: 10.1007/s10787-021-00839-2. Epub 2021 Jul 9.

Real-world effectiveness of BNT162b2 mRNA vaccine: a meta-analysis of large observational studies

Chia Siang Kow  1   2 , Syed Shahzad Hasan  3   4
Affiliations
Meta-Analysis

Real-world effectiveness of BNT162b2 mRNA vaccine: a meta-analysis of large observational studies

Chia Siang Kow et al. Inflammopharmacology. 2021 Aug.

Abstract

This paper aims to summarize through meta-analyses the overall vaccine effectiveness of the BNT162b2 mRNA vaccine from observational studies. A systematic literature search with no language restriction was performed in electronic databases to identify eligible observational studies which reported the adjusted effectiveness of the BNT162b2 mRNA vaccine to prevent RT-PCR confirmed COVID-19. Meta-analyses with the random-effects model were used to calculate the pooled hazard ratio (HR) and pooled incidence rate ratio (IRR) at 95% confidence intervals, and the vaccine effectiveness was indicated as (pooled HR - 1)/HR or (pooled IRR - 1)/IRR. Nineteen studies were included for this meta-analysis. The meta-analysis revealed significant protective effect against RT-PCR confirmed COVID-19 ≥ 14 days after the first dose, with vaccine effectiveness of 53% (95% confidence interval 32-68%), and ≥ 7 days after the second dose, with vaccine effectiveness of 95% (95% confidence interval: 96-97%). Despite its effectiveness, reporting vaccine safety data by relevant stakeholders should be encouraged as BNT162b2 mRNA is a new vaccine that has not gained full approval. There have been limited data about vaccine effectiveness among immunocompromised patients; thus, the vaccine should be used cautiously in this patient population.

Keywords: BNT162b2; COVID-19; Real world; SARS-CoV-2; Vaccine.

PubMed Disclaimer

Conflict of interest statement

The authors report no conflict of interest.

Figures

Fig. 1
Fig. 1
PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) flow diagram of process of study selection
Fig. 2
Fig. 2
Pooled hazard ratio (HR) of the incidence of COVID-19 14 as well as 21 days post first dose of vaccine (A) and 7 as well as 14 days post second dose of vaccine (B) relative to no vaccination
Fig. 3
Fig. 3
Pooled incident rate ratio (IRR) of the incidence of COVID-19 14 as well as 21 days post first dose of vaccine (A) and 7 as well as 14 days post second dose of vaccine (B) relative to no vaccination
See this image and copyright information in PMC

References

    1. Angel Y, Spitzer A, Henig O, Saiag E, Sprecher E, Padova H, Ben-Ami R (2021) Association between vaccination with BNT162b2 and incidence of symptomatic and asymptomatic SARS-CoV-2 infections among health care workers. JAMA 325:2457–2465 - PMC - PubMed
    1. Björk J, Inghammar M, Moghaddassi M, Rasmussen M, Malmqvist U, Kahn F (2021) Effectiveness of the BNT162b2 vaccine in preventing COVID-19 in the working age population-first results from a cohort study in Southern Sweden. Preprint. medRxiv 2021.04.20.21254636 - PubMed
    1. Cabezas C, Coma E, Mora-Fernandez N, Li X, Martinez-Marcos M, Fina-Aviles F, Fabregas M, Hermosilla E, Jover A, Contel JC, Lejardi Y (2021) Effects of BNT162b2 mRNA Vaccination on COVID-19 Disease, Hospitalisation and Mortality in Nursing Homes and Healthcare Workers: a Prospective Cohort Study Including 28,594 Nursing Home Residents, 26,238 Nursing Home Staff, and 61,951 Healthcare Workers in Catalonia. Preprint. SSRN ssrn.3815682 - PMC - PubMed
    1. Chung H, He S, Nasreen S, Sundaram M, Buchan S, Wilson S, Chen B, Calzavara A, Fell D, Austin PC, Wilson K (2021) Effectiveness of BNT162b2 and mRNA-1273 COVID-19 vaccines against symptomatic SARS-CoV-2 infection and severe COVID-19 outcomes in Ontario, Canada. Preprint. medRxiv 2021.05.24.21257744 - PMC - PubMed
    1. Dagan N, Barda N, Kepten E, Miron O, Perchik S, Katz MA, Hernán MA, Lipsitch M, Reis B, Balicer RD. BNT162b2 mRNA Covid-19 vaccine in a nationwide mass vaccination setting. N Engl J Med. 2021;384:1412–1423. doi: 10.1056/NEJMoa2101765. - DOI - PMC - PubMed

MeSH terms

LinkOut - more resources