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NCT04505722 · ClinicalTrials.gov registry record · Phase 3

A Study of Ad26.COV2.S for the Prevention of SARS-CoV-2-Mediated COVID-19 in Adult Participants

A Phase 3 study of Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol, sponsored by Janssen Vaccines & Prevention B.V..

Completed
Registry status
Phase 3
Development phase
44,325
Enrollment target
20
Study locations

NCT04505722: Completed Phase 3 study of Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol, sponsored by Janssen Vaccines & Prevention B.V..

NCT04505722 is a Phase 3 study of Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol that has completed, run by Janssen Vaccines & Prevention B.V.. The registered enrollment target is 44,325 participants, above the 769-participant average among 15,282 other Phase 3 trials with a reported enrollment target (5664% higher). The trial reports 20 study locations across 5 states. According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04505722, a Phase 3 study of Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol, has completed, sponsored by Janssen Vaccines & Prevention B.V..

COMPLETED
Registry status
Phase 3
Development phase
44,325 participants
Enrollment target
20
Study locations

Study Summary

The study will evaluate the efficacy of Ad26.COV2.S in the prevention of molecularly confirmed moderate to severe/critical COVID-19, as compared to placebo, in adult participants.

Primary Outcome

Molecularly confirmed moderate to severe/critical COVID-19 was defined as a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) positive reverse transcription/polymerase chain reaction (RT-PCR) or molecular test result from any available respiratory tract sample (example, nasal swab sample, sputum sample, throat swab sample, saliva sample) or other sample. Moderate included one sign or symptom such as respiratory rate \>= 20 breaths per minute and symptoms such as shortness of breath or

Interventions

  • OTHER Placebo
  • BIOLOGICAL Ad26.COV2.S

Study Locations (20)

California

  • Anaheim Clinical Trials, LLC - Anaheim
  • Ark Clinical Research - Long Beach
  • Anthony Mills Medical, Inc - Los Angeles
  • Stanford University Medical Center - Palo Alto
  • UCSD Antiviral Research Center AVRC - San Diego
  • Wr McCr Llc - San Diego
  • VA Medical Center - San Francisco

Arizona

  • Synexus Clinical Research US Inc - Glendale
  • VA Medical Center - Phoenix
  • Central Phoenix Medical Clinic - Phoenix
  • Quality of Life Medical & Research Center, LLC - Tucson
  • Synexus Clinical Research US Inc - Tucson

Alabama

  • Synexus Clinical Research US Inc - Birmingham
  • University of Alabama Birmingham - Birmingham
  • Alabama Vaccine Research Clinic at UAB - Birmingham
  • Optimal Research - Huntsville

Arkansas

  • University of Arkansas for Medical Sciences - Little Rock
  • Central Arkansas Veterans Healthcare System - Little Rock

Colorado

  • Childrens Hospital Colorado - Aurora
  • Rocky Mountain Regional VA Medical Center - Denver

Trial Details

FieldValue
Enrollment Target 44,325 participants
Start Date 2020-09-07
Est. Completion 2023-03-31
Phase Phase 3
Janssen Vaccines & Prevention B.V.

34 total trials

What the finished NCT04505722 record still lists

NCT04505722 is an interventional study that assigns participants to a tested intervention. Its 44,325 participants enrollment target places it among the larger protocols in the corpus, above the 769-participant average among 15,282 other Phase 3 trials with a reported enrollment target (5664% higher).

The record links to 1 condition, with Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.

NCT04505722 names 20 study sites across 5 states, led by California, Arizona, Alabama.

Frequently Asked Questions

What is clinical trial NCT04505722 about?

NCT04505722 is a clinical study titled "A Study of Ad26.COV2.S for the Prevention of SARS-CoV-2-Mediated COVID-19 in Adult Participants". The study will evaluate the efficacy of Ad26.COV2.S in the prevention of molecularly confirmed moderate to severe/critical COVID-19, as compared to placebo, in adult participants.

What is the current status of trial NCT04505722?

This trial is currently completed. It is a Phase 3 study. The enrollment target is 44,325 participants. The study started on 2020-09-07. Estimated completion is 2023-03-31.

What conditions does trial NCT04505722 study?

This clinical trial studies the following conditions: Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol.

What interventions are being tested in trial NCT04505722?

The interventions under investigation include: Placebo (OTHER), Ad26.COV2.S (BIOLOGICAL).

Who is sponsoring clinical trial NCT04505722?

This trial is sponsored by Janssen Vaccines & Prevention B.V., which has 34 total clinical trials registered on ClinicalTrials.gov.

Where is trial NCT04505722 being conducted?

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

How this trial's enrollment target compares

Where NCT04505722's enrollment target sits among peer trials

44,325 3rd of 2000 higher than 1,998 of 2,000 other Phase 3 trials

participants (enrollment target), bucketed by value

Each bar is a band; taller bars hold more other Phase 3 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 NCT04505722, the US trial registry maintained by the National Library of Medicine. NCT04505722 (large enrollment · wide site footprint · completed) retrieved and formatted by PlainTrial, see methodology.