Evidence map›Paper›PMID 33798499›Full record

Trial reportLancet (London, England)2021

Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 variant of concern 202012/01 (B.1.1.7): an exploratory analysis of a randomised controlled trial.

Katherine R W Emary, Tanya Golubchik, Parvinder K Aley, Cristina V Ariani, Brian Angus, Sagida Bibi, Beth Blane, David Bonsall, Paola Cicconi, Sue Charlton and 57 more

2 registry-linked trialsOpen access · hybridAbstract readClinical Trial, Phase IIClinical Trial, Phase IIIMulticenter Study
PubMed Full text at PMC Publisher
In one paragraph

Trial report in Lancet (London, England), 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to 2 registered trials, which are not on this map. Cited by 396 papers, 13 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
396citing papers in PubMed, 13 pooled it
40.8field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

NCT04400838 phase2 / phase3completednot on this map

A Phase 2/3 Study to Determine the Efficacy, Safety and Immunogenicity of the Candidate Coronavirus Disease (COVID-19) Vaccine ChAdOx1 nCoV-19

TypeinterventionalSponsorUniversity of OxfordRan2020 to 2025Enrolled10,811ConditionsCoronavirusArmsChAdOx1 nCoV-19 (Abs 260), MenACWY vaccine, ChAdOx1 nCoV-19 (Abs 260) + 2.2x10^10vp (qPCR) boost, Two dose MenACWY vaccine, ChAdOx1 nCoV-19 (qPCR)
NCT04912700 completednot on this map

The Impact of Vaccination on Severity of Illness in COVID-19: A Multicenter Cohort Study

TypeobservationalSponsorCorewell Health EastRan2021 to 2021Enrolled11,834ConditionsCovid19ArmsCOVID-19 vaccine
3 · Its place in the literature

Who cites it

396 citing papers in PubMed, 13 syntheses or guidelines pooled it, 651 citations in OpenAlex.

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  4. Assessing the robustness of COVID-19 vaccine efficacy trials: systematic review and meta-analysis, January 2023.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2023
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  9. Efficacy and safety of COVID-19 vaccines.The Cochrane database of systematic reviews · 2022
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336 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

67 authors at 20 institutions in 2 countries.

Katherine R W EmaryOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Tanya GolubchikBig Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Parvinder K AleyOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Cristina V ArianiWellcome Sanger Institute, Wellcome Genome Campus, Hinxton, UK.
Brian AngusJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Sagida BibiOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Beth BlaneCOVID-19 Genomics UK, Department of Medicine, University of Cambridge, Cambridge, UK.
David BonsallWellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Paola CicconiJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Sue CharltonNational Infection Service, Public Health England, Salisbury, UK.
Elizabeth A ClutterbuckOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Andrea M CollinsDepartment of Clinical Sciences, Liverpool School of Tropical Medicine and Liverpool University Hospitals NHS Foundation Trust, Liverpool, UK.
Tony CoxUK Biocentre, Milton Keynes, UK.
Thomas C DartonDepartment of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK; Department of Infection and Tropical Medicine, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK.
Christina DoldOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Alexander D DouglasJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Christopher J A DuncanDepartment of Infection and Tropical Medicine, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK; Translational and Clinical Research Institute, Immunity and Inflammation Theme, Newcastle University, Newcastle upon Tyne, UK.
Katie J EwerJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Amy L FlaxmanJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Saul N FaustNIHR Southampton Clinical Research Facility and Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust; Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
Daniela M FerreiraDepartment of Clinical Sciences, Liverpool School of Tropical Medicine and Liverpool University Hospitals NHS Foundation Trust, Liverpool, UK.
Shuo FengOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Adam FinnUniversity Hospitals Bristol and Weston NHS Foundation Trust, Bristol, UK.
Pedro M FolegattiJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Michelle FuskovaJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Eva GalizaSt George's Vaccine Institute, St George's, University of London, London, UK.
Anna L GoodmanDepartment of Infection, Guy's and St Thomas' NHS Foundation Trust, St Thomas' Hospital, London, UK; MRC Clinical Trials Unit, University College London, London, UK.
Catherine M GreenClinical BioManufacturing Facility, University of Oxford, Oxford, UK.
Christopher A GreenNIHR/Wellcome Trust Clinical Research Facility, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK.
Melanie GreenlandOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Bassam HallisNational Infection Service, Public Health England, Salisbury, UK.
Paul T HeathSt George's Vaccine Institute, St George's, University of London, London, UK.
Jodie HayUniversity of Glasgow, Glasgow, UK; Lighthouse Laboratory in Glasgow, Queen Elizabeth University Hospital, Glasgow, UK.
Helen C HillDepartment of Clinical Sciences, Liverpool School of Tropical Medicine and Liverpool University Hospitals NHS Foundation Trust, Liverpool, UK.
Daniel JenkinJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Simon KerridgeOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Rajeka LazarusSevern Pathology, North Bristol NHS Trust, Bristol, UK.
Vincenzo LibriNIHR UCLH Clinical Research Facility, London, UK; NIHR UCLH Biomedical Research Centre, London, UK.
Patrick J LillieHull University Teaching Hospitals NHS Trust, Hull, UK.
Catherine LuddenCOVID-19 Genomics UK, Department of Medicine, University of Cambridge, Cambridge, UK.
Natalie G MarchevskyOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Angela M MinassianJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Alastair C McGregorLondon Northwest University Healthcare, Harrow, UK.
Yama F MujadidiOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Daniel J PhillipsOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Emma PlestedOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Katrina M PollockNIHR Imperial Clinical Research Facility, London, UK; NIHR Imperial Biomedical Research Centre, London, UK.
Hannah RobinsonOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Andrew SmithCollege of Medical, Veterinary & Life Sciences, Glasgow Dental Hospital and School, University of Glasgow, Glasgow, UK.
Rinn SongOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Matthew D SnapeOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Rebecca K SutherlandClinical Infection Research Group, Regional Infectious Diseases Unit, Western General Hospital, Edinburgh, UK.
Emma C ThomsonMRC University of Glasgow Centre for Virus Research, Glasgow, UK; Severn Pathology, North Bristol NHS Trust, Bristol, UK; Department of Infectious Diseases, Queen Elizabeth University Hospital, Glasgow, UK.
Mark ToshnerHeart Lung Research Institute, Department of Medicine, University of Cambridge, Cambridge, UK; NIHR Cambridge Clinical Research Facility, Cambridge, UK; Cambridge University Hospital and Royal Papworth NHS Foundation Trusts, Cambridge, UK.
David P J TurnerUniversity of Nottingham, Nottingham, UK; Nottingham University Hospitals NHS Trust, Nottingham, UK.
Johan VekemansAstraZeneca BioPharmaceuticals, Gaithersburg, MD, USA.
Tonya L VillafanaAstraZeneca BioPharmaceuticals, Gaithersburg, MD, USA.
Christopher J WilliamsPublic Health Wales, Cardiff, UK; Aneurin Bevan University Health Board, Newport, UK.
Adrian V S HillJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Teresa LambeOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Sarah C GilbertJenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Merryn VoyseyOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
Maheshi N RamasamyOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK. Electronic address: maheshi.ramasamy@paediatrics.ox.ac.uk.
Andrew J PollardOxford Vaccine Group, Department of Paediatrics, University of Oxford, Oxford, UK.
COVID-19 Genomics UK consortium
AMPHEUS Project
Oxford COVID-19 Vaccine Trial Group
University of Oxford · GBJenner Institute · GBLiverpool School of Tropical Medicine · GBAstraZeneca (United States) · USPublic Health England · GBSt George's, University of London · GBUniversity of Cambridge · GBUniversity of Glasgow · GBAneurin Bevan University Health Board · GBBiocentre Technology (United Kingdom) · GBGenomics England · GBLondon North West Healthcare NHS Trust · GBNewcastle University · GBNIHR Imperial Biomedical Research Centre · GBNorth Bristol NHS Trust · GBNottingham University Hospitals NHS Trust · GBOpen Data Institute · GBQueen Elizabeth University Hospital · GBSheffield Teaching Hospitals NHS Foundation Trust · GBSt Thomas' Hospital · GB

Funding

Medical Research Council MC_PC_19026Medical Research Council MC_PC_19027Medical Research Council MC_PC_19055Medical Research Council MC_UU_00004/04Medical Research Council MC_UU_12023/22Wellcome Trust 211153/Z/18/Z
6 · The paper itself

Abstract

backgroundA new variant of SARS-CoV-2, B.1.1.7, emerged as the dominant cause of COVID-19 disease in the UK from November, 2020. We report a post-hoc analysis of the efficacy of the adenoviral vector vaccine, ChAdOx1 nCoV-19 (AZD1222), against this variant.

methodsVolunteers (aged ≥18 years) who were enrolled in phase 2/3 vaccine efficacy studies in the UK, and who were randomly assigned (1:1) to receive ChAdOx1 nCoV-19 or a meningococcal conjugate control (MenACWY) vaccine, provided upper airway swabs on a weekly basis and also if they developed symptoms of COVID-19 disease (a cough, a fever of 37·8°C or higher, shortness of breath, anosmia, or ageusia). Swabs were tested by nucleic acid amplification test (NAAT) for SARS-CoV-2 and positive samples were sequenced through the COVID-19 Genomics UK consortium. Neutralising antibody responses were measured using a live-virus microneutralisation assay against the B.1.1.7 lineage and a canonical non-B.1.1.7 lineage (Victoria). The efficacy analysis included symptomatic COVID-19 in seronegative participants with a NAAT positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to vaccine received. Vaccine efficacy was calculated as 1 - relative risk (ChAdOx1 nCoV-19 vs MenACWY groups) derived from a robust Poisson regression model. This study is continuing and is registered with ClinicalTrials.gov, NCT04400838, and ISRCTN, 15281137.

findingsParticipants in efficacy cohorts were recruited between May 31 and Nov 13, 2020, and received booster doses between Aug 3 and Dec 30, 2020. Of 8534 participants in the primary efficacy cohort, 6636 (78%) were aged 18-55 years and 5065 (59%) were female. Between Oct 1, 2020, and Jan 14, 2021, 520 participants developed SARS-CoV-2 infection. 1466 NAAT positive nose and throat swabs were collected from these participants during the trial. Of these, 401 swabs from 311 participants were successfully sequenced. Laboratory virus neutralisation activity by vaccine-induced antibodies was lower against the B.1.1.7 variant than against the Victoria lineage (geometric mean ratio 8·9, 95% CI 7·2-11·0). Clinical vaccine efficacy against symptomatic NAAT positive infection was 70·4% (95% CI 43·6-84·5) for B.1.1.7 and 81·5% (67·9-89·4) for non-B.1.1.7 lineages.

interpretationChAdOx1 nCoV-19 showed reduced neutralisation activity against the B.1.1.7 variant compared with a non-B.1.1.7 variant in vitro, but the vaccine showed efficacy against the B.1.1.7 variant of SARS-CoV-2.

fundingUK Research and Innovation, National Institute for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midlands NIHR Clinical Research Network, and AstraZeneca.

Indexed as

AdolescentAdultAntibodies, NeutralizingChAdOx1 nCoV-19COVID-19COVID-19 Nucleic Acid TestingCOVID-19 VaccinesFemaleHumansMaleMiddle AgedNucleic Acid Amplification TechniquesPandemicsSARS-CoV-2Single-Blind MethodUnited KingdomAntibodies, NeutralizingChAdOx1 nCoV-19COVID-19 Vaccines

Identifiers

PMID33798499
PMCPMC8009612
OpenAlexW3152490217

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.