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NCT04516746 · ClinicalTrials.gov registry record · Phase 3

Phase III Double-blind, Placebo-controlled Study of AZD1222 for the Prevention of COVID-19 in Adults

A Phase 3 study of COVID-19 and SARS-CoV-2, sponsored by AstraZeneca.

Completed
Registry status
Phase 3
Development phase
32,450
Enrollment target
20
Study locations

NCT04516746: Completed Phase 3 study of COVID-19 and SARS-CoV-2, sponsored by AstraZeneca.

NCT04516746 is a Phase 3 study of COVID-19 and SARS-CoV-2 that has completed, run by AstraZeneca. The registered enrollment target is 32,450 participants, below the 38,356-participant average among 298 other COVID-19 trials with a reported enrollment target (15% lower). The trial reports 20 study locations across 8 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04516746, a Phase 3 study of COVID-19 and SARS-CoV-2, has completed, sponsored by AstraZeneca.

COMPLETED
Registry status
Phase 3
Development phase
32,450 participants
Enrollment target
20
Study locations

Study Summary

The aim of the study is to assess the safety, efficacy, and immunogenicity of AZD1222 for the prevention of COVID-19.

Primary Outcome

A binary response, whereby a participant with negative serostatus at baseline is defined as a COVID-19 case if their first case of SARS-CoV-2 RT-PCR-positive symptomatic illness occurs ≥ 15 days post second dose of study intervention. Otherwise, a participant is not defined as a COVID-19 case. The primary efficacy analysis was performed once approximately 150 events meeting the primary efficacy outcome measure definition had occurred across the AZD1222 and placebo groups.

Conditions Studied

Interventions

  • BIOLOGICAL Placebo
  • BIOLOGICAL AZD1222

Study Locations (20)

California

  • Research Site - Berkeley
  • Research Site - El Centro
  • Research Site - Los Angeles
  • Research Site - Los Angeles
  • Research Site - San Diego
  • Research Site - San Diego
  • Research Site - San Francisco
  • Research Site - San Francisco
  • Research Site - Torrance

Florida

  • Research Site - Coral Gables
  • Research Site - Lake Worth
  • Research Site - Miami Lakes
  • Research Site - Orlando

Arizona

  • Research Site - Phoenix
  • Research Site - Scottsdale

Arkansas

  • Research Site - Little Rock

Colorado

  • Research Site - Denver

Connecticut

  • Research Site - Danbury

Hawaii

  • Research Site - Honolulu

Idaho

  • Research Site - Meridian

Trial Details

FieldValue
Enrollment Target 32,450 participants
Start Date 2020-08-28
Est. Completion 2023-02-10
Phase Phase 3
AstraZeneca

1,285 total trials

What the finished NCT04516746 record still lists

NCT04516746 is an interventional study that assigns participants to a tested intervention. Its 32,450 participants enrollment target places it among the larger protocols in the corpus, below the 38,356-participant average among 298 other COVID-19 trials with a reported enrollment target (15% lower).

The record links to 2 conditions, with COVID-19 appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.

NCT04516746 names 20 study sites across 8 states, led by California, Florida, Arizona.

Frequently Asked Questions

What is clinical trial NCT04516746 about?

NCT04516746 is a clinical study titled "Phase III Double-blind, Placebo-controlled Study of AZD1222 for the Prevention of COVID-19 in Adults". The aim of the study is to assess the safety, efficacy, and immunogenicity of AZD1222 for the prevention of COVID-19.

What is the current status of trial NCT04516746?

This trial is currently completed. It is a Phase 3 study. The enrollment target is 32,450 participants. The study started on 2020-08-28. Estimated completion is 2023-02-10.

What conditions does trial NCT04516746 study?

This clinical trial studies the following conditions: COVID-19, SARS-CoV-2.

What interventions are being tested in trial NCT04516746?

The interventions under investigation include: Placebo (BIOLOGICAL), AZD1222 (BIOLOGICAL).

Who is sponsoring clinical trial NCT04516746?

This trial is sponsored by AstraZeneca, which has 1,285 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT04516746 being conducted?

This trial has 20 study locations across Arizona, Arkansas, California, Colorado, Connecticut. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.

Similar trials for COVID-19

Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.

Where NCT04516746's enrollment target sits among peer trials

32,450 11th of 298 higher than 288 of 298 other COVID-19 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other COVID-19 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov registry export · 2026-08-08

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Source: ClinicalTrials.gov NCT04516746, the US trial registry maintained by the National Library of Medicine. NCT04516746 (large enrollment · wide site footprint · completed) retrieved and formatted by PlainTrial, see methodology.