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NCT04898023 · ClinicalTrials.gov registry record · Phase 2
Zinc and Green Tea Extract for Community Respiratory Viral Infections
A Phase 2 study, sponsored by University of Missouri-Columbia.
- Terminated
- Registry status
- Phase 2
- Development phase
- 17
- Enrollment target
NCT04898023: Clinical Trial Phase 2 study, sponsored by University of Missouri-Columbia.
NCT04898023 is a Phase 2 study that was terminated before completion, run by University of Missouri-Columbia. The registered enrollment target is 17 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (87% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04898023, a Phase 2 study, was terminated before completion, sponsored by University of Missouri-Columbia.
- TERMINATED
- Registry status
- Phase 2
- Development phase
- 17 participants
- Enrollment target
Study Summary
Zinc and green tea supplementation have both been independently studied for supporting immune health during cold and flu-like illness in non-hospitalized patients with clinical trials demonstrating promising but inconsistent results. Combination therapy may offer an improved effect as the antioxidant compounds found in green tea have been shown to increase cellular zinc concentrations thereby inhibiting viral replication. This study seeks to evaluate the effect of combination supplementation using established doses of zinc and green tea extract on symptom duration and severity from cold and flu-like illness, including COVID-19, in adult community patients enrolled in a randomized placebo-controlled trial.
Primary Outcome
Recovery is defined as achieving a daily total symptom severity score of 0 or 1 within 7 days using an established 12 symptom scoring system, with a severity score ranging from 0-absent to 3-very severe for each symptom assessed (max of 36 points possible; higher scores indicate a greater severity of symptoms)
Interventions
- DRUG Placebo
- DRUG zinc-green tea extract-ascorbic acid
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 17 participants |
| Start Date | 2022-09-21 |
| Est. Completion | 2023-12-20 |
| Phase | Phase 2 |
Why NCT04898023 stopped before completion
NCT04898023 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 17 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (87% lower).
The record links to 0 conditions, and to 2 interventions - of which Placebo is the first listed.
NCT04898023 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04898023 about?
NCT04898023 is a clinical study titled "Zinc and Green Tea Extract for Community Respiratory Viral Infections". Zinc and green tea supplementation have both been independently studied for supporting immune health during cold and flu-like illness in non-hospitalized patients with clinical trials demonstrating promising but inconsistent results. Combination therapy may offer an improved effect as the antioxidan...
What is the current status of trial NCT04898023?
This trial is currently terminated. It is a Phase 2 study. The enrollment target is 17 participants. The study started on 2022-09-21. Estimated completion is 2023-12-20.
What interventions are being tested in trial NCT04898023?
The interventions under investigation include: Placebo (DRUG), zinc-green tea extract-ascorbic acid (DRUG).
Who is sponsoring clinical trial NCT04898023?
This trial is sponsored by University of Missouri-Columbia, which has 291 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04898023's enrollment target sits among peer trials
17 1903rd of 2000 higher than 93 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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