Cited by 633SARS-CoV-2 and COVID-19 ResearchCOVID-19 Clinical Research StudiesCOVID-19 epidemiological studies

What defines an efficacious COVID-19 vaccine? A review of the challenges assessing the clinical efficacy of vaccines against SARS-CoV-2

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Hodgson, Susanne H, Mansatta, Kushal, Mallett, Garry, Harris, Victoria, Emary, Katherine R W, Pollard, Andrew J·2021·The Lancet Infectious Diseases

Abstract

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused more than 1 million deaths in the first 6 months of the pandemic and huge economic and social upheaval internationally. An efficacious vaccine is essential to prevent further morbidity and mortality. Although some countries might deploy COVID-19 vaccines on the strength of safety and immunogenicity data alone, the goal of vaccine development is to gain direct evidence of vaccine efficacy in protecting humans against SARS-CoV-2 infection and COVID-19 so that manufacture of efficacious vaccines can be selectively upscaled. A candidate vaccine against SARS-CoV-2 might act against infection, disease, or transmission, and a vaccine capable of reducing any of these elements could contribute to disease control. However, the most important efficacy endpoint, protection against severe disease and death, is difficult to assess in phase 3 clinical trials. In this Review, we explore the challenges in assessing the efficacy of candidate SARS-CoV-2 vaccines, discuss the caveats needed to interpret reported efficacy endpoints, and provide insight into answering the seemingly simple question, "Does this COVID-19 vaccine work?"

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  1. [71]Yu J Tostanoski LH Peter L DNA vaccine protection against SARS-CoV-2 in rhesus macaques Science 369 2020 806 811 32434945 PMC7243363

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Authors
Hodgson, S. H., Mansatta, K., Mallett, G., Harris, V., Emary, K. R. W., & Pollard, A. J.
Affiliations
University of Oxford (GB)
Corresponding author
Hodgson, Susanne H
Venue
The Lancet Infectious Diseases
Publisher
Elsevier BV
Published
2021-02
Volume
21
Issue
2
Pages
e26-e35
ISSN
1473-3099 (ISSN-L)
OpenAlex
W3088489318
Cited by
633
References
79
Citations by year
2026: 11 · 2025: 14 · 2024: 52 · 2023: 99 · 2022: 221 · 2021: 221 · 2020: 14
FWCI
6.56
Type
journal article
Language
en
Open access
Locations
  • The Lancet Infectious Diseases (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • UK Research and Innovation (MC_PC_19055)
  • Coalition for Epidemic Preparedness Innovations
  • National Institute for Health Research
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
Keywords
COVID-19 vaccines, SARS-CoV-2, vaccine efficacy, efficacy endpoints, vaccine development
MeSH terms
Immunogenicity, Vaccine, COVID-19, SARS-CoV-2, COVID-19 Vaccines, Clinical Trials as Topic, Humans, Research Design, Vaccination, Treatment Outcome, Outcome Assessment, Health Care

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