deltatrials
Completed PHASE3 INTERVENTIONAL 2-arm NCT04516746

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

A Phase III Randomized, Double-blind, Placebo-controlled Multicenter Study in Adults, to Determine the Safety, Efficacy, and Immunogenicity of AZD1222, a Non-replicating ChAdOx1 Vector Vaccine, for the Prevention of COVID-19

Sponsor: AstraZeneca

Conditions COVID-19 SARS-CoV-2
Interventions AZD1222 Placebo
Updated 20 times since 2020 Last updated: Feb 2, 2024 Started: Aug 28, 2020 Primary completion: Mar 5, 2021 Completion: Feb 10, 2023
This information is for research purposes only and is not medical advice. Consult a healthcare provider before making any medical decision.

This PHASE3 trial investigates COVID-19 and SARS-CoV-2 and is currently completed. AstraZeneca leads this study, which shows 20 recorded versions since 2020 — indicating substantial longitudinal coverage. Longitudinal tracking of infectious disease trials helps identify durability of treatment effects.

Status Flow

~Sep 2020 – ~Nov 2020 · 2 months · monthly snapshot~Nov 2020 – ~Dec 2020 · 30 days · monthly snapshot~Dec 2020 – ~Jan 2021 · 31 days · monthly snapshot~Jan 2021 – ~Feb 2021 · 31 days · monthly snapshot~Feb 2021 – ~Mar 2021 · 28 days · monthly snapshot~Mar 2021 – ~Apr 2021 · 31 days · monthly snapshot~Apr 2021 – ~May 2021 · 30 days · monthly snapshot~May 2021 – ~Sep 2021 · 4 months · monthly snapshot~Sep 2021 – ~Jan 2022 · 4 months · monthly snapshot~Jan 2022 – ~Mar 2022 · 59 days · monthly snapshot~Mar 2022 – ~May 2022 · 2 months · monthly snapshot~May 2022 – ~Sep 2022 · 4 months · monthly snapshot~Sep 2022 – ~Nov 2022 · 2 months · monthly snapshot~Nov 2022 – ~Feb 2023 · 3 months · monthly snapshot~Feb 2023 – ~May 2023 · 3 months · monthly snapshot~May 2023 – ~Mar 2024 · 10 months · monthly snapshot~Mar 2024 – ~Jul 2024 · 4 months · monthly snapshot~Jul 2024 – ~Sep 2024 · 2 months · monthly snapshot~Sep 2024 – ~Sep 2025 · 12 months · monthly snapshot~Sep 2025 – present · 10 months · monthly snapshot

Change History

20 versions recorded

  1. Sep 2025 — Present [monthly]

    Completed PHASE3

  2. Sep 2024 — Sep 2025 [monthly]

    Completed PHASE3

  3. Jul 2024 — Sep 2024 [monthly]

    Completed PHASE3

  4. Mar 2024 — Jul 2024 [monthly]

    Completed PHASE3

  5. May 2023 — Mar 2024 [monthly]

    Completed PHASE3

    Status: Active Not Recruiting → Completed

▶ Show 15 earlier versions

  1. Feb 2023 — May 2023 [monthly]

    Active Not Recruiting PHASE3

  2. Nov 2022 — Feb 2023 [monthly]

    Active Not Recruiting PHASE3

  3. Sep 2022 — Nov 2022 [monthly]

    Active Not Recruiting PHASE3

  4. May 2022 — Sep 2022 [monthly]

    Active Not Recruiting PHASE3

  5. Mar 2022 — May 2022 [monthly]

    Active Not Recruiting PHASE3

  6. Jan 2022 — Mar 2022 [monthly]

    Active Not Recruiting PHASE3

  7. Sep 2021 — Jan 2022 [monthly]

    Active Not Recruiting PHASE3

  8. May 2021 — Sep 2021 [monthly]

    Active Not Recruiting PHASE3

  9. Apr 2021 — May 2021 [monthly]

    Active Not Recruiting PHASE3

  10. Mar 2021 — Apr 2021 [monthly]

    Active Not Recruiting PHASE3

    Status: Recruiting → Active Not Recruiting

  11. Feb 2021 — Mar 2021 [monthly]

    Recruiting PHASE3

  12. Jan 2021 — Feb 2021 [monthly]

    Recruiting PHASE3

  13. Dec 2020 — Jan 2021 [monthly]

    Recruiting PHASE3

  14. Nov 2020 — Dec 2020 [monthly]

    Recruiting PHASE3

    Status: Not Yet Recruiting → Recruiting

  15. Sep 2020 — Nov 2020 [monthly]

    Not Yet Recruiting PHASE3

    First recorded

Aug 2020

Trial started

Per CT.gov start date — pre-dates our first snapshot

Eligibility Summary

No eligibility information available.

Contact Information

Sponsor contact:
  • AstraZeneca
  • Iqvia Pty Ltd
Data source: AstraZeneca

For direct contact, visit the study record on ClinicalTrials.gov .

Study Locations

Albuquerque, United States , Ankeny, United States , Ann Arbor, United States , Austin, United States , Baltimore, United States , Berkeley, United States , Berlin, United States , Bethesda, United States , Boston, United States , Brooklyn, United States and 64 more locations