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NCT04999111 · ClinicalTrials.gov registry record · Phase 2
A Study of Ad26.COV2.S Administered as Booster Vaccination in Adults Who Have Previously Received Primary Vaccination With Ad26.COV2.S or BNT162b2
A Phase 2 study of Coronavirus Disease, sponsored by Janssen Vaccines & Prevention B.V..
- Completed
- Registry status
- Phase 2
- Development phase
- 1,541
- Enrollment target
- 20
- Study locations
NCT04999111: Completed Phase 2 study of Coronavirus Disease, sponsored by Janssen Vaccines & Prevention B.V..
NCT04999111 is a Phase 2 study of Coronavirus Disease that has completed, run by Janssen Vaccines & Prevention B.V.. The registered enrollment target is 1,541 participants, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (1059% higher). The trial reports 20 study locations across 11 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04999111, a Phase 2 study of Coronavirus Disease, has completed, sponsored by Janssen Vaccines & Prevention B.V..
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 1,541 participants
- Enrollment target
- 20
- Study locations
Study Summary
The purposes of this study are to demonstrate the non-inferiority (NI) of the neutralizing antibody response to the original strain 14 days after booster vaccination with Ad26.COV2.S at the different dose levels, administered greater than or equal to (\>=) 6 months after single-dose primary vaccination with Ad26.COV2.S, compared to the neutralizing antibody response to the original strain induced by single-dose primary vaccination with Ad26.COV2.S; To demonstrate the NI of the neutralizing antibody response to the leading variant of high consequence or concern 14 days after booster vaccination with Ad26.COV2.S at the 5\*10\^10 virus particle (vp) dose level, administered \>= 6 months after single-dose primary vaccination with Ad26.COV2.S (5\*10\^10 vp dose level), compared to the neutralizing antibody response to the leading variant of high consequence or concern induced by single-dose primary vaccination with Ad26.COV2.S at the 5\*10\^10 vp dose level, if feasible; To demonstrate the NI of the neutralizing antibody response to the original strain 14 days after booster vaccination with Ad26.COV2.S at the different dose levels administered \>=6 months after completing a 2-dose primary vaccination with Pfizer BNT162b2, compared to the neutralizing antibody response to the original strain induced by 2-dose primary vaccination with Pfizer BNT162b2; To demonstrate the NI of neutralizing antibody response to the leading variant of high consequence or concern 14 days after booster vaccination with Ad26.COV2.S at the 5\*10\^10 vp dose level, administered \>= 6 months after completing a 2-dose primary vaccination with Pfizer BNT162b2, compared to the neutralizing antibody response to the leading variant of high consequence or concern induced by 2-dose primary vaccination with Pfizer BNT162b2, if feasible.
Primary Outcome
Percentage of participants with serological response against SARS-CoV-2 original strain (Wuhan, 2019, whole genome sequence) 14 days after Ad26.COV2.S booster vaccination after completing primary vaccination with Ad26.COV2.S was reported. A participant was considered a responder if one or both of the following conditions were satisfied: (1) Pre-booster titer less than (\<) lower limit of quantification (LLOQ) and post-booster titer greater than or equal to (\>=) 4\*LLOQ or (2) Pre-booster titer
Conditions Studied
Interventions
- BIOLOGICAL Ad26.COV2.S
Study Locations (20)
Florida
- Velocity Clinical Research, Hallandale Beach - Hallandale
- Research Centers of America, LLC - Hollywood
- Synexus Clinical Research US Inc - Orlando
- Synexus Clinical Research US Inc - The Villages
California
- Anaheim Clinical Trials, LLC - Anaheim
- Ark Clinical Research - Long Beach
- Velocity Clinical Research - North Hollywood
South Carolina
- Velocity Clinical Research, Anderson - Anderson
- Accellacare US Inc - Mt. Pleasant
- Coastal Carolina Research Center - North Charleston
Arizona
- Central Phoenix Medical Clinic - Phoenix
- Synexus Clinical Research US Inc - Tucson
Massachusetts
- Massachusetts General Hospital - Boston
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center - Boston
Illinois
- Optimal Research - Peoria
Kansas
- Johnson County Clin-Trials - Lenexa
Kentucky
- University of Kentucky - Lexington
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 1,541 participants |
| Start Date | 2021-08-06 |
| Est. Completion | 2022-11-22 |
| Phase | Phase 2 |
What the finished NCT04999111 record still lists
NCT04999111 is an interventional study that assigns participants to a tested intervention. Its 1,541 participants enrollment target places it among the larger protocols in the corpus, above the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (1059% higher).
The record links to 1 condition, with Coronavirus Disease appearing as the primary indexed condition, and to 1 intervention - of which Ad26.COV2.S is the first listed.
NCT04999111 names 20 study sites across 11 states, led by Florida, California, South Carolina.
Frequently Asked Questions
What is clinical trial NCT04999111 about?
NCT04999111 is a clinical study titled "A Study of Ad26.COV2.S Administered as Booster Vaccination in Adults Who Have Previously Received Primary Vaccination With Ad26.COV2.S or BNT162b2". The purposes of this study are to demonstrate the non-inferiority (NI) of the neutralizing antibody response to the original strain 14 days after booster vaccination with Ad26.COV2.S at the different dose levels, administered greater than or equal to (\>=) 6 months after single-dose primary vaccinat...
What is the current status of trial NCT04999111?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 1,541 participants. The study started on 2021-08-06. Estimated completion is 2022-11-22.
What conditions does trial NCT04999111 study?
This clinical trial studies the following conditions: Coronavirus Disease.
What interventions are being tested in trial NCT04999111?
The interventions under investigation include: Ad26.COV2.S (BIOLOGICAL).
Who is sponsoring clinical trial NCT04999111?
This trial is sponsored by Janssen Vaccines & Prevention B.V., which has 34 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT04999111 being conducted?
This trial has 20 study locations across Arizona, California, Florida, Illinois, Kansas. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04999111's enrollment target sits among peer trials
1,541 11th of 2000 higher than 1,990 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 2 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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