# A Study of Ad26.COV2.S Administered as Booster Vaccination in Adults Who Have Previously Received Primary Vaccination With Ad26.COV2.S or BNT162b2

> **NCT04999111** · PHASE2 · COMPLETED · sponsor: **Janssen Vaccines & Prevention B.V.** · enrollment: 1541 (actual)

## Conditions studied

- Coronavirus Disease

## Interventions

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

## Key facts

- **NCT ID:** NCT04999111
- **Lead sponsor:** Janssen Vaccines & Prevention B.V.
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2021-08-06
- **Primary completion:** 2021-10-27
- **Final completion:** 2022-11-22
- **Target enrollment:** 1541 (ACTUAL)
- **Last updated:** 2025-02-04


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04999111

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04999111, "A Study of Ad26.COV2.S Administered as Booster Vaccination in Adults Who Have Previously Received Primary Vaccination With Ad26.COV2.S or BNT162b2". Retrieved via AI Analytics 2026-06-03 from https://api.ai-analytics.org/clinical/NCT04999111. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*