A Phase 2 interventional study of Clinical Observation and Patient Observation in Prostate Adenocarcinoma, PSA Failure and PSA Progression, sponsored by City of Hope Medical Center. Suspended at 7 sites in United States. Open to male participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-10.
Sponsored by City of Hope Medical Center · Phase 2, Interventional, and Treatment
This phase II trial studies how well white button mushroom supplement works in reducing prostate-specific antigen (PSA) levels in patients with prostate cancer that has come back (recurrent) or has favorable risk and has not undergone any therapy (therapy naive). PSA is a blood marker of prostate growth. White button mushroom supplement may affect PSA level, various parameters of immune system and levels of hormones that may have a role in prostate cancer growth.
PRIMARY OBJECTIVES:
I. To assess the proportion of patients with any prostate specific antigen (PSA) reduction at 12 weeks (\~3 months) in observation + white button mushroom (WBM) supplement arm and observation only arm (control arm). (Cohort 1) II. To assess relative change in PSA at 48 weeks (\~12 months) from baseline with or without WBM treatment. (Cohort 2)
SECONDARY OBJECTIVES:
I. To evaluate, adverse events, PSA-response rate and time to PSA progression. (Cohort 1) II. To evaluate adverse events, time to initiation of additional therapy and progression. (Cohort 2)
EXPLORATORY OBJECTIVES:
I. To characterize the immunomodulatory effects of WBM supplement in serial blood samples. (Cohort 1) II. To assess the effect of therapy with WBM on sexual function. (Cohort 1) III. To assess the effect of WBM on Gleason grade in prostate cancer subjects on active surveillance. (Cohort 2) IV. To characterize the immunomodulatory effects of WBM supplement in serial blood samples and in tumor tissue. (Cohort 2) V. To characterize changes in cancer signaling pathways in tumor tissue after intake of WBM supplement. (Cohort 2) VI. To assess the effect of WBM supplement on sexual function. (Cohort 2)
OUTLINE: Patients are assigned to 1 of 2 cohorts.
COHORT I: Biochemically recurrent prostate cancer patients are randomized to 1 of 2 arms.
ARM IA: Patients receive white button mushroom extract orally (PO) twice daily (BID) on day 1. Treatment repeats every 4 weeks for cycles 1-3 then every 12 weeks for cycles 4-6 (36 weeks) in the absence of disease progression or unacceptable toxicity.
ARM IB: Patients undergo clinical observation for 12 weeks. If PSA continues to increase, patients have the option to receive the white button mushroom extract as in arm IA.
COHORT II: Therapy naive favorable risk prostate cancer patients are randomized to 1 of 2 arms.
ARM IIA: Patients receive white mushroom extract PO BID on day 1. Treatment repeats every 12 weeks for 4 cycles (48 weeks) in the absence of disease progression or unacceptable toxicity.
ARM IIB: Patients undergo active surveillance for 48 weeks.
After completion of study treatment, patients are followed up at 30 days.
6,367 studies on the registry are indexed under Prostatic Neoplasms; 1,397 are open to participants now.
This study's enrollment of 133 is above the median of 58 across 4,821 interventional studies indexed under Prostatic Neoplasms.
Browse Prostatic Neoplasms studies →City of Hope Medical Center is the lead sponsor of 670 studies on the registry; 181 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 12 (40%) have results posted.
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BIOCHEMICALLY RECURRENT PROSTATE CANCER COHORT (COHORT 1) ONLY: PSA failure defined as:
BIOCHEMICALLY RECURRENT PROSTATE CANCER COHORT (COHORT 1) ONLY: Received any number of primary local therapies, defined as:
THERAPY NAIVE FAVORABLE RISK PROSTATE CANCER COHORT (COHORT 2) ONLY: Clinical stage T1c-T2a as defined below:
THERAPY NAIVE FAVORABLE RISK PROSTATE CANCER COHORT (COHORT 2) ONLY: No prior therapy for prostate cancer defined as:
Exclusion Criteria:
BIOCHEMICALLY RECURRENT PROSTATE CANCER COHORT (COHORT 1) ONLY: Prior therapy for recurrent prostate cancer (unless given as a component of attempted curative salvage treatment including salvage radiation therapy, and completed > 6 months before day 1 of protocol therapy):
Patients receive white button mushroom extract PO BID on day 1. Treatment repeats every 4 weeks for cycles 1-3 then every 12 weeks for cycles 4-6 (36 weeks) in the absence of disease progression or unacceptable toxicity.
Other: Questionnaire Administration · Drug: White Button Mushroom Extract
Patients undergo clinical observation for 12 weeks. If PSA continues to increase, patients have the option to receive the white button mushroom extract as in arm IA.
Other: Clinical Observation · Other: Questionnaire Administration
Patients receive white mushroom extract PO BID on day 1. Treatment repeats every 12 weeks for 4 cycles (48 weeks) in the absence of disease progression or unacceptable toxicity.
Other: Questionnaire Administration · Drug: White Button Mushroom Extract
Patients undergo active surveillance for 48 weeks.
Other: Patient Observation · Other: Questionnaire Administration
Undergo clinical observation
Also known as: observation
Undergo active surveillance
Also known as: Active Surveillance, deferred therapy, expectant management, observation, Watchful Waiting
Ancillary studies
Given PO
Also known as: WBM Extract
Prostate-specific antigen (PSA) (ng/mL) levels (Cohort 1)
For continuous variables, descriptive statistics (number \[n\], mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: At 12 weeks
Relative change in PSA (Cohort 2)
The relative difference in PSA will be measured as log (48 week PSA/baseline PSA). Undetectable PSA at 48 weeks will be coded as the low end of the lab measurement range for PSA. This measure of relative difference will be compared between the white button supplement (WBM) + active surveillance and active surveillance only patients. For continuous variables, descriptive statistics (n, mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: Baseline up to 48 weeks
Incidence of adverse events
Will be defined per National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0. Grade 2 serious adverse events and all grade 3-5 adverse events will be reported in the e-case report forms. Observed toxicities will be summarized in terms of type (organ affected or laboratory determination), severity, attribution, time of onset, probable association with the study treatment and reversibility or outcome.
Time frame: Up to 48 weeks
Proportion of patients with PSA response (Cohort 1)
Will be defined as the sum of complete (PSA-normalization) and partial responders (PSA-partial response) vs non-responders. For continuous variables, descriptive statistics (number \[n\], mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: Up to 48 weeks
Time to PSA progression (Cohort 1)
For continuous variables, descriptive statistics (number \[n\], mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: Time from randomization to PSA progression, assessed up to 48 weeks
Time to initiation of additional therapy (Cohort 2)
For continuous variables, descriptive statistics (n, mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: Baseline up to 48 weeks
Time to progression (Cohort 2)
Will be defined as any Gleason grade 4 or 5 upon repeat biopsy or conversion from 3+4 to 4+3 or higher, prostate cancer is found in a greater number of prostate biopsy cores, prostate cancer occupies a greater extent of the prostate biopsy cores, PSA \> 100 ng/mL. For continuous variables, descriptive statistics (n, mean, standard deviation, standard error, median range) will be provided. For categorical variables, patient counts and percentages will be provided.
Time frame: From randomization to progression, assessed up to 48 weeks
Change in temporal levels of circulating myeloid-derived suppressor cells (MDSCs)
Will be studies within the peripheral blood mononuclear cell (PBMC) compartment. Will evaluate the relative change in prostate cancer-associated MDSCs after 12 weeks of WBM supplement intake in borderline resectable pancreatic cancer patients versus in those on observation using a two group t-test. Results for cohort 1 will be confirmed by analyzing prostate cancer-associated MDSCs in cohort 2 as well (change from baseline to 48 weeks).
Time frame: Baseline to 48 weeks
Change in temporal levels of pro-/anti-inflammatory mediators
Will include cytokines/growth factors/chemokines, including IL-15 in plasma. Will evaluate the baseline correlatives and the relative role of treatment in a multivariate exploratory analysis.
Time frame: Baseline up to 48 weeks
Sexual function
Will be evaluated by the sexual function questionnaire, including the Sexual Health Inventory for Men score. The Sexual Health Inventory for Men (SHIM) Questionnaire scoring system will be used.
Time frame: Up to 48 weeks
This study is suspended, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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City of Hope Medical Center