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Grape Seed Extract in Treating Patients with Asymptomatic or Minimally Symptomatic Prostate Cancer

Trial Status: Active

This phase II trial studies how well grape seed extract works in treating patients with prostate cancer without symptoms or with minimal symptoms. Grape seed extract may prevent prostate cancer growth and progression.

Inclusion Criteria

  • Written informed consent has been obtained
  • Histologically confirmed prostate adenocarcinoma
  • Evidence of rising PSA, on 2 separate occasions, at least one week apart; baseline PSA must be >= 0.2 ng/mL at the time of screening; radiographic evidence of disease is not allowed
  • Patients must have sufficient PSA time points prior to enrollment (a minimum of 3 PSA levels within a six month period) to calculate a baseline PSA doubling time
  • Patients must not be on active luteinizing hormone-releasing hormone (LHRH) agonist/antagonist therapy and must have testosterone level > 50 ng/dL
  • Patients must not be on active anti-androgen therapy or 5-alpha reductase inhibitors; patients on stable dose of 5-alpha reductase inhibitors for benign prostatic hypertrophy for at least 12 months may continue; they must withdraw from the study if this is stopped while on study
  • Patients who are candidates for local salvage therapy must have had this option pursued or discussed; and the patient must have either declined salvage therapy or was deemed not to be a candidate for salvage therapy
  • Patients who have PSA recurrence after local salvage therapy may participate in this study
  • Patients with hormone sensitive disease who received prior androgen deprivation therapy as part of primary/salvage local treatment or patients receiving intermittent androgen deprivation therapy will be allowed to participate
  • Eastern Cooperative Oncology Group (ECOG) performance status 0-2
  • Absolute neutrophil count (ANC) >= 1,500 cells/uL
  • Hemoglobin >= 9 g/dL
  • Platelets >= 75,000/uL
  • Serum creatinine =< 2 x the upper limit of normal (ULN)
  • Total bilirubin =< 2 x upper limit of normal (ULN)
  • Alanine aminotransferase (ALT) =< 3 x ULN, aspartate aminotransferase (AST) =< 3 x ULN
  • Patients can continue taking what they are taking at the time they start on the study, but agree not to start any new (over the counter) herbal supplement on regular basis during study duration
  • Prior chemotherapy for prostate cancer (upfront, adjuvant, etc.) is allowed as long as it was not given for hormone-refractory disease

Exclusion Criteria

  • Patients who are on active surveillance for untreated localized disease may not participate in this study
  • Inability to swallow gelatin capsules, or any medical condition that interferes with normal gastrointestinal absorption
  • Major surgery, radiation, or treatment with any other investigational drug within 2 weeks of study treatment
  • Documented hypersensitivity reaction to any product with GSE
  • Known chronic infection with human immunodeficiency virus (HIV) or viral hepatitis
  • Symptomatic prostate cancer as determined by cancer-related pain requiring narcotic pain medication or any other clear and unequivocal symptoms related to prostate cancer
  • History of another cancer is exclusionary unless it is believed to be likely cured or is unlikely to be fatal in the next 3 years (e.g. squamous cell carcinoma, superficial bladder cancer, chronic lymphocytic leukemia, etc)
  • Very fast PSA doubling time of less than 4 weeks, if the absolute PSA is > 2 ng/mL or an absolute PSA value of greater than or equal to 20 ng/ml
  • Known allergy/intolerance to soy, phosphatidylcholine or any other constituents of grape seed extract


University of Colorado Hospital
Status: ACTIVE
Contact: Paul Daniel Maroni
Phone: 303-724-2712
Fort Collins
Poudre Valley Hospital
Status: ACTIVE
Contact: Steven Robert Schuster
Phone: 970-493-6337
Medical Center of the Rockies
Status: ACTIVE
Contact: Paul Daniel Maroni
Phone: 720-724-2712


I. To determine the efficacy, based on increase in prostate specific antigen doubling time (PSADT), of grape seed extract (GSE) product in patients with hormone-sensitive, non-metastatic prostate cancer.


I. To evaluate efficacy, based on prostate specific antigen (PSA) response, PSA velocity (the rate of change of PSA over time), and duration of PSA response.

II. To explore potential biomarkers of response and antioxidant effects, dietary effects, and other correlative studies.


Patients receive prostate specific GSE orally (PO) twice daily (BID). Treatment continues for up to 1 year in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up every 6 weeks for 3 months and then every 3 months for up to 1 year.

Trial Phase Phase II

Trial Type Treatment

Lead Organization
University of Colorado Hospital

Principal Investigator
Paul Daniel Maroni

  • Primary ID 16-0607
  • Secondary IDs NCI-2017-00906
  • ID NCT03087903