Zinc and Green Tea Extract for Community Respiratory Viral Infections

Evaluation of Combination Zinc and Green Tea Extract Supplementation on Reduction in Symptom Duration and Severity Associated With Community Respiratory Viral Infections: a Randomized Control Trial (ZiPhenol Study)

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.

Inclusion Criteria:

1. Provision of signed and dated informed consent form
2. Stated willingness to comply with all study procedures and availability for the duration of the study
3. Male or female, aged 18 years and older
4. Ability to take oral medication and be willing to adhere to the prescribed dosing regimen
5. Self-reported cold or flu symptoms for < 72 hours

Exclusion Criteria:

1. Pregnant or actively seeking to become pregnant
2. Positive for influenza with planned treatment with oseltamivir or baloxavir
3. Current or planned treatment with an FDA regulated drug (including those under EUA) for COVID-19
4. Chronic liver disease (i.e. baseline liver function tests (LFTs) > 1.5x the upper limit of normal (ULN) or established cirrhosis
5. Chronic renal failure stage 4 or greater
6. History of kidney stones
7. Acute secondary bacterial infection at the time of enrollment
8. Requiring hospitalization for any reason at the time of enrollment
9. History of copper or iron deficiency
10. Current prescription for quinolone antibiotics, tetracycline antibiotics, or penicillamine at the time of enrollment
11. Allergy/intolerance to any of the active ingredients under investigation including zinc citrate, green tea, and ascorbic acid (vitamin C)
12. Patients without decision making capacity
13. Currently enrolled in another clinical trial for a respiratory viral infection