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

> **NCT04505722** · PHASE3 · COMPLETED · sponsor: **Janssen Vaccines & Prevention B.V.** · enrollment: 44325 (actual)

## Conditions studied

- Participants With or Without Stable Co-morbidities Associated With Progression to Severe COVID-19 at Different Stages of the Protocol

## Interventions

- **BIOLOGICAL:** Ad26.COV2.S
- **OTHER:** Placebo

## Key facts

- **NCT ID:** NCT04505722
- **Lead sponsor:** Janssen Vaccines & Prevention B.V.
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2020-09-07
- **Primary completion:** 2023-03-31
- **Final completion:** 2023-03-31
- **Target enrollment:** 44325 (ACTUAL)
- **Last updated:** 2025-02-04


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04505722

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04505722, "A Study of Ad26.COV2.S for the Prevention of SARS-CoV-2-Mediated COVID-19 in Adult Participants". Retrieved via AI Analytics 2026-06-24 from https://api.ai-analytics.org/clinical/NCT04505722. Licensed CC0.

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