Vitamin D and Soy Supplements in Treating Patients With Recurrent Prostate Cancer

Phase II Trial of Vitamin D and Soy Supplementation for Biochemically Recurrent Prostate Cancer Following Definitive Local Therapy

RATIONALE: Vitamin D and soy extract may be effective in lowering prostate-specific antigen (PSA) levels in patients with recurrent prostate cancer that has not responded to previous treatment.

PURPOSE: This phase II trial is studying how well giving vitamin D together with soy supplements works in treating patients with recurrent prostate cancer.

Study Overview

• Status: Completed
• Conditions: Prostate Cancer
• Intervention / Treatment: Dietary supplement: Vitamin D; Dietary supplement: soy

Detailed Description

OBJECTIVES:

• Test the response of biochemically recurrent prostate cancer to a combination of cholecalciferol (i.e., vitamin D) and soy isoflavones (i.e., soy extract) after failed definitive local therapy as determined by PSA response.

OUTLINE: Patients receive oral cholecalciferol twice daily and a soy supplement (i.e., soy bar or shake) once daily. Treatment continues for 3-12 months in the absence of disease progression or unacceptable toxicity.

Blood samples are obtained at baseline and periodically during study to measure serum PSA, serum calcium, plasma cholecalciferol, and plasma soy isoflavone levels. Blood samples are also analyzed for expression of cholecalciferol receptor, p21, and p27 in peripheral blood lymphocytes as surrogate markers of the actions of cholecalciferol and genistein. Protein expression is assessed by immunoblot analysis of cell lysates as well as quantitative polymerase chain reaction.

Patients complete a toxicity questionnaire once each month to assess for cholecalciferol and soy supplementation toxicities and symptoms of hypercalcemia.

After completion of study therapy, patients are followed every 3 months for 1 year.

• Study Type: Interventional
• Enrollment (Actual): 26
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Winston-Salem, North Carolina, United States, 27157-1096
      • Wake Forest University Comprehensive Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 120 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Male

Description

Inclusion:

• Age > 18 years
• Histologically confirmed adenocarcinoma of the prostate
• Biochemical relapse following definitive therapy by ASTRO criteria (PSA with 3 consecutive rising measurements separated by at least one month) and minimum PSA ≥ 1.0 ng/mL
• PSA doubling time of ≥ 6 months, as demonstrated by 3 PSA measurements obtained ≥ 2 months apart
• No hormonal therapy in 6 months prior to enrollment
• ECOG performance status 0-2
• Life expectancy > 3 months
• At least 2 years since prior definitive radiotherapy
• No concurrent cholecalciferol, calcium, or soy supplements
• Absolute granulocyte count ≥ 1,000/mm³
• Platelet count ≥ 100,000/mm³
• Hemoglobin ≥ 9.0 g/dL
• Creatinine ≤ 2.0 mg/dL
• Total bilirubin ≤ 2.0 mg/dL
• Calcium > 8.5 mg/dL and < 10.5 mg/dL
• Testosterone ≥ 150 ng/dL

Exclusion:

• No clinically evident brain metastases
• Concurrent cholecalciferol, calcium, or soy supplements
• Concurrent chemotherapy with nonstudy drugs
• Serious medical illness that would limit survival to < 3 months, or psychiatric condition that would preclude giving informed consent
• Other malignancy except nonmelanoma skin cancer, adequately treated stage I or II cancer from which the patient is currently in complete remission, or any other cancer from which the patient has been disease-free for the past 5 years
• Active, uncontrolled bacterial, viral, or fungal infection
• Hemorrhagic disorder
• Evidence of metastatic disease by bone scan or CT scan
• History of hypercalcemia
• More History of exposure to other phytotherapeutics, including PC-SPES and Saw Palmetto, within the last year.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Soy and Vitamin D; Patients will receive oral supplementation with both 2,000 IU per day of vitamin D (cholecalciferol) and soy (160 mg per day soy isoflavones). Serum PSA and plasma levels of vitamin D will be assessed monthly. Soy isoflavones levels will be assessed every three months.	Dietary supplement: Vitamin D; Patients will receive oral supplementation of 2,000 IU per day of vitamin D (cholecalciferol); Other Names: cholecalciferol; Dietary supplement: soy; Patients will receive oral supplementation of soy (160 mg per day soy isoflavones).; Other Names: isoflavones

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Number of Participants Showing a 50% Reduction in Serum Prostate Specific Antigen(PSA) During Treatment	up to one year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in PSA Slope		up to one year
Changes in PSA Doubling Time		up to one year
Number of Adverse Events, Grades 1-5	Toxicity will be graded according to the revised NCI Common Terminology Criteria for Adverse Events v 3.0, (CTCAE). Number of events with grade 1-5 will be reported.	up to one year
Time to Progression	Progression will be defined as a 50% rise in serum PSA compared to the baseline value confirmed on at least two measurements at least two weeks apart.	up to three years

Collaborators and Investigators

• Sponsor: Wake Forest University Health Sciences
• Collaborators: National Cancer Institute (NCI)
• Investigators: Study Chair: K.C. Balaji, MD, Wake Forest University Health Sciences

Study record dates

Study Major Dates

• Study Start: April 1, 2007
• Primary Completion (Actual): December 1, 2012
• Study Completion (Actual): December 1, 2012

Study Registration Dates

• First Submitted: July 10, 2007
• First Submitted That Met QC Criteria: July 10, 2007
• First Posted (Estimate): July 11, 2007

Study Record Updates

• Last Update Posted (Actual): November 21, 2018
• Last Update Submitted That Met QC Criteria: October 25, 2018
• Last Verified: October 1, 2018

More Information

Terms related to this study

• Keywords: stage III prostate cancer; adenocarcinoma of the prostate; stage I prostate cancer; stage II prostate cancer
• Additional Relevant MeSH Terms: Neoplasms; Urogenital Neoplasms; Neoplasms by Site; Genital Neoplasms, Male; Prostatic Diseases; Prostatic Neoplasms; Physiological Effects of Drugs; Micronutrients; Vitamins; Bone Density Conservation Agents; Calcium-Regulating Hormones and Agents; Vitamin D; Cholecalciferol
• Other Study ID Numbers: IRB00000371; P30CA012197 (U.S. NIH Grant/Contract); CCCWFU-85106; CCCWFU-IRB00000371

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No