Green tea and quercetin with docetaxel for metastatic castration-resistant prostate cancer.

A Phase I/II Study to Determine the Safety and Efficacy of a Combination of Green Tea and Quercetin With Docetaxel in Castration-resistant Prostate Cancer Patients

PHASE1; PHASE2 · Charles Drew University of Medicine and Science · NCT06615752

This will test whether adding green tea and quercetin to docetaxel chemotherapy helps men with metastatic castration-resistant prostate cancer more than docetaxel with a placebo.

Quick facts

PhasePHASE1; PHASE2
Study typeInterventional
Enrollment99 (estimated)
Ages18 Years and up
SexMale
SponsorCharles Drew University of Medicine and Science (other)
Drugs / interventionschemotherapy, prednisone
Locations1 site (Los Angeles, California)
Trial IDNCT06615752 on ClinicalTrials.gov

What this trial studies

Men with metastatic castration-resistant prostate cancer who are starting docetaxel plus prednisone are assigned to receive either green tea with quercetin or a matched placebo alongside their chemotherapy. The study includes an initial phase to establish safety and dosing followed by a phase focused on whether the combination improves therapeutic outcomes compared with placebo. Investigators will monitor side effects, blood counts, liver tests, and measures of cancer response during treatment. Primary outcomes include tolerability and anti-tumor activity such as response rates and disease progression.

Who should consider this trial

Good fit: Men aged 18 or older with metastatic castration-resistant prostate cancer who are about to start docetaxel (and have adequate bone marrow and liver function and are on medical or surgical castration) are ideal candidates.

Not a fit: Patients who are not starting docetaxel, who have poor bone marrow or liver function, or who have non-metastatic disease are unlikely to benefit from this combination approach.

Why it matters

Potential benefit: If successful, adding green tea and quercetin could increase the effectiveness of docetaxel, potentially improving response or slowing disease progression.

How similar studies have performed: Preclinical studies and limited early clinical work suggest green tea compounds and quercetin have anti-cancer activity, but clinical evidence that adding them to chemotherapy improves outcomes in advanced prostate cancer is still limited.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Signed and dated informed consent form and HIPPA (Health Insurance Portability and Accountability Act) authorization.
* Stated willingness to comply with all study procedures and availability for the duration of the study.
* Male patients 18 years or older
* Diagnosed with metastatic prostate cancer
* History of confirmed progressive disease with concurrent use of medical castration (e.g. luteinizing hormone-releasing hormone analogue), or surgical castration
* Confirmed progressive disease with concurrent use of enzalutamide, apalutamide, darolutamide, and/or abiraterone acetate
* Clinical decision to start doc infusion with prednisone treatment
* Adequate bone marrow function (absolute neutrophil count (ANC) more than1500 cells/mm³, platelet count more than 100,000 cells/mm³)
* Adequate liver function (total bilirubin less than upper limit of normal (ULN), alanine aminotransferase (ALT) less than 1.5 x ULN, aspartate aminotransferase (AST) less than 1.5 x ULN)
* Adequate renal function (serum creatinine level within normal limits)
* At least a 6-month or greater life expectancy
* Willing to stop consuming tea or tea-containing products and quercetin supplements throughout the entire intervention period except for the green tea extract and quercetin provided during study intervention

Exclusion Criteria:

* Prior treatment of chemotherapy and/or radiotherapy for metastatic disease
* Any comorbid condition that would preclude the administration of docetaxel/prednisone
* Ongoing alcohol abuse
* Significant medical or psychiatric conditions that would make the patient a poor protocol candidate
* Prior allergic reaction to tea, tea products or quercetin supplements
* Allergies to multiple food items or nutritional supplements

Where this trial is running

Los Angeles, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Metastatic Castration-resistant Prostate Cancer, green tea, quercetin, docetaxel, prostate cancer, phase II

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.