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NCT04811664 · ClinicalTrials.gov registry record · Phase 3
A Study of SARS CoV-2 Infection and Potential Transmission in Individuals Immunized With Moderna COVID-19 Vaccine
A Phase 3 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- Completed
- Registry status
- Phase 3
- Development phase
- 1,923
- Enrollment target
NCT04811664: Completed Phase 3 study, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
NCT04811664 is a Phase 3 study that has completed, run by National Institute of Allergy and Infectious Diseases (NIAID). The registered enrollment target is 1,923 participants, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (149% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04811664, a Phase 3 study, has completed, sponsored by National Institute of Allergy and Infectious Diseases (NIAID).
- COMPLETED
- Registry status
- Phase 3
- Development phase
- 1,923 participants
- Enrollment target
Study Summary
The purpose of this study is to assess SARS CoV-2 infection, viral shedding, and subsequent potential transmission in individuals immunized with the Moderna COVID-19 vaccine.
Primary Outcome
Incidence of SARS-CoV-2 infection diagnosed by study PCR among baseline negative participants, with exposure starting from first study PCR and censored at last PCR/outside vaccination and exposure period for the Immediate arm additionally limited to period after the second vaccine dose (period unrestricted for Standard of Care and Vaccine Declined arms: by definition corresponds to unvaccinated exposure). Exact confidence interval.
Interventions
- BIOLOGICAL Moderna COVID-19 Vaccine
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 1,923 participants |
| Start Date | 2021-03-24 |
| Est. Completion | 2021-12-30 |
| Phase | Phase 3 |
What the finished NCT04811664 record still lists
NCT04811664 is an interventional study that assigns participants to a tested intervention. Its 1,923 participants enrollment target places it among the larger protocols in the corpus, above the 772-participant average among 15,282 other Phase 3 trials with a reported enrollment target (149% higher).
The record links to 0 conditions, and to 1 intervention - of which Moderna COVID-19 Vaccine is the first listed.
NCT04811664 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04811664 about?
NCT04811664 is a clinical study titled "A Study of SARS CoV-2 Infection and Potential Transmission in Individuals Immunized With Moderna COVID-19 Vaccine". The purpose of this study is to assess SARS CoV-2 infection, viral shedding, and subsequent potential transmission in individuals immunized with the Moderna COVID-19 vaccine.
What is the current status of trial NCT04811664?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 1,923 participants. The study started on 2021-03-24. Estimated completion is 2021-12-30.
What interventions are being tested in trial NCT04811664?
The interventions under investigation include: Moderna COVID-19 Vaccine (BIOLOGICAL).
Who is sponsoring clinical trial NCT04811664?
This trial is sponsored by National Institute of Allergy and Infectious Diseases (NIAID), which has 2,006 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04811664's enrollment target sits among peer trials
1,923 109th of 2000 higher than 1,892 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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