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AZD1222 vs Placebo: Number of Participants With First COVID-19 Symptomatic Illness Using University of Oxford-Defined Symptom Criteria Post Second Dose of Study Intervention

Calculated by ConductScience from the counts the trial posted to ClinicalTrials.gov.

Measures 6

Calculated by ConductScience from the counts the trial posted to ClinicalTrials.gov.

MeasureValue95% interval, lower95% interval, upperMethodNoteSource
Risk in group 10.004870.003940.00601wilsonClinicalTrials.gov
Risk in group 20.01590.01350.0188wilsonClinicalTrials.gov
Risk difference, group 1 minus group 2-0.011-0.0141-0.00834newcombe hybrid scoreClinicalTrials.gov
Risk ratio, group 1 over group 20.3060.2340.401logClinicalTrials.gov
Odds ratio, group 1 over group 20.3030.2310.397logClinicalTrials.gov
Number needed to treat, for one fewer participant with the outcome on AZD1222 than on Placebo90.671.1120from the risk difference intervalClinicalTrials.gov

Groups 2

Group 2 names the comparator: placebo.

GroupTitleDescriptionWith the outcomeAnalysedClinicalTrials.gov codeSource
Group 1AZD1222Participants were randomized to receive 2 IM doses of 5\*10\^10 vp (nominal, ± 1.5\*10\^10 vp) AZD1222 on Days 1 and 29.8617,662OG000ClinicalTrials.gov
Group 2PlaceboParticipants were randomized to receive 2 IM doses of placebo matching with AZD1222 on Days 1 and 29.1368,550OG001ClinicalTrials.gov

Outcome 5

FieldValueSource
TypeSECONDARYClinicalTrials.gov
TitleNumber of Participants With First COVID-19 Symptomatic Illness Using University of Oxford-Defined Symptom Criteria Post Second Dose of Study InterventionClinicalTrials.gov
Description
The incidence of the first case of SARS-CoV-2 RT-PCR-positive symptomatic illness occurring ≥ 15 days post second dose of study intervention using University of Oxford-defined symptom criteria: new onset of fever (\> 100 °Fahrenheit \[\> 37.8 °Celsius\]), cough, shortness of breath, or anosmia/ageusia.
ClinicalTrials.gov
Time frameFrom 15 days post second dose up to DCO of 05 March 2021 or study discontinuation or unblinding or receipt of non-study COVID-19 vaccination, up to a maximum of 17 weeksClinicalTrials.gov
Population
The FVS included all participants in the FAS who were seronegative at baseline, received 2 doses of study intervention, and who remained on-study 15 days after their second dose without having had a prior SARS-CoV-2 RT-PCR-positive confirmed COVID-19 infection.
ClinicalTrials.gov

Trial 8

FieldValueSource
TitlePhase III Double-blind, Placebo-controlled Study of AZD1222 for the Prevention of COVID-19 in AdultsClinicalTrials.gov
NCT numberNCT04516746ClinicalTrials.gov
PhasesPHASE3ClinicalTrials.gov
ConditionsCOVID-19, SARS-CoV-2ClinicalTrials.gov
InterventionsAZD1222, PlaceboClinicalTrials.gov
Lead sponsorAstraZenecaClinicalTrials.gov
Results first posted2022-04-01ClinicalTrials.gov
Results on ClinicalTrials.govhttps://clinicaltrials.gov/study/NCT04516746?tab=resultsClinicalTrials.gov

Source 4

FieldValueSource
Releasetrial-comparisons-2026-03-23-0.1.0ClinicalTrials.gov
Release manifest SHA-256f66225897fbf258b57ea10bdacfd0347d3cdfda93f7f5685234b7e06ea36fa57ClinicalTrials.gov
AACT copy2026-03-23ClinicalTrials.gov
Tables readoutcome_counts.parquet, outcome_measurements.parquet, outcomes.parquet, reported_event_totals.parquet, reported_events.parquet, result_groups.parquet, studies.parquet, ctgov_trial.parquetClinicalTrials.gov

The same record as JSON

Release trial-comparisons-2026-03-23-0.1.0

ClinicalTrials.gov's posted results, through CTTI's AACT: ClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299 ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions. The measures are ConductScience's calculation from them.

ClinicalTrials.gov: none stated ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions. The measures are ConductScience's calculation from them.