AZD1222 vs Placebo: Number of Participants With COVID-19 Symptomatic Illness Post First 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.
| Measure | Value | 95% interval, lower | 95% interval, upper | Method | Note | Source |
|---|---|---|---|---|---|---|
| Risk in group 1 | 0.0139 | 0.0124 | 0.0156 | wilson | ClinicalTrials.gov | |
| Risk in group 2 | 0.0294 | 0.0263 | 0.0329 | wilson | ClinicalTrials.gov | |
| Risk difference, group 1 minus group 2 | -0.0155 | -0.0192 | -0.012 | newcombe hybrid score | ClinicalTrials.gov | |
| Risk ratio, group 1 over group 2 | 0.474 | 0.404 | 0.556 | log | ClinicalTrials.gov | |
| Odds ratio, group 1 over group 2 | 0.466 | 0.396 | 0.549 | log | ClinicalTrials.gov | |
| Number needed to treat, for one fewer participant with the outcome on AZD1222 than on Placebo | 64.6 | 52 | 83.7 | from the risk difference interval | ClinicalTrials.gov |
Groups 2
Group 2 names the comparator: placebo.
| Group | Title | Description | With the outcome | Analysed | ClinicalTrials.gov code | Source |
|---|---|---|---|---|---|---|
| Group 1 | AZD1222 | Participants were randomized to receive 2 IM doses of 5\*10\^10 vp (nominal, ± 1.5\*10\^10 vp) AZD1222 on Days 1 and 29. | 287 | 20,589 | OG000 | ClinicalTrials.gov |
| Group 2 | Placebo | Participants were randomized to receive 2 IM doses of placebo matching with AZD1222 on Days 1 and 29. | 303 | 10,300 | OG001 | ClinicalTrials.gov |
Outcome 5
| Field | Value | Source |
|---|---|---|
| Type | SECONDARY | ClinicalTrials.gov |
| Title | Number of Participants With COVID-19 Symptomatic Illness Post First Dose of Study Intervention | ClinicalTrials.gov |
| Description | The incidence of SARS-CoV-2 RT-PCR-positive symptomatic illness occurring post first dose of study intervention. | ClinicalTrials.gov |
| Time frame | From Day 1 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 approximately 27 weeks | ClinicalTrials.gov |
| Population | The FAS included all randomized participants who received at least 1 dose of study intervention, irrespective of their protocol adherence and continued participation in the study. Only participants who are seronegative at baseline were analyzed. | ClinicalTrials.gov |
Trial 8
| Field | Value | Source |
|---|---|---|
| Title | Phase III Double-blind, Placebo-controlled Study of AZD1222 for the Prevention of COVID-19 in Adults | ClinicalTrials.gov |
| NCT number | NCT04516746 | ClinicalTrials.gov |
| Phases | PHASE3 | ClinicalTrials.gov |
| Conditions | COVID-19, SARS-CoV-2 | ClinicalTrials.gov |
| Interventions | AZD1222, Placebo | ClinicalTrials.gov |
| Lead sponsor | AstraZeneca | ClinicalTrials.gov |
| Results first posted | 2022-04-01 | ClinicalTrials.gov |
| Results on ClinicalTrials.gov | https://clinicaltrials.gov/study/NCT04516746?tab=results | ClinicalTrials.gov |
Source 4
| Field | Value | Source |
|---|---|---|
| Release | trial-comparisons-2026-03-23-0.1.0 | ClinicalTrials.gov |
| Release manifest SHA-256 | f66225897fbf258b57ea10bdacfd0347d3cdfda93f7f5685234b7e06ea36fa57 | ClinicalTrials.gov |
| AACT copy | 2026-03-23 | ClinicalTrials.gov |
| Tables read | outcome_counts.parquet, outcome_measurements.parquet, outcomes.parquet, reported_event_totals.parquet, reported_events.parquet, result_groups.parquet, studies.parquet, ctgov_trial.parquet | ClinicalTrials.gov |
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.