Evaluating PSMA Changes in Prostate Cancer After Hormonal Therapy

Modulation of PSMA Expression in Castration Sensitive and Castration Resistant Prostate Cancer in Response to Hormonal Therapy

Phase 4 Interventional OHSU Knight Cancer Institute · NCT05919329

This study is testing how hormonal therapy changes a specific protein in men with prostate cancer to see if those changes can help doctors understand the cancer better.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment80 (estimated)
Ages18 Years and up
SexMale
SponsorOHSU Knight Cancer Institute Academic / other
Drugs / interventionsradiation
Locations1 site (Portland, Oregon)
Trial IDNCT05919329 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates how hormonal therapy affects prostate-specific membrane antigen (PSMA) expression in patients with both Castration Sensitive Prostate Cancer (CSPC) and Castration Resistant Prostate Cancer (CRPC). The study aims to assess PSMA modulation at two time points: 8 days and 28 days after therapy initiation. Additionally, it will evaluate whether changes in PSMA expression influence tumor staging as determined by PSMA PET imaging. Participants will be monitored for up to 5 years to gather comprehensive data on the effects of hormonal therapy on PSMA levels and their prognostic implications.

Who should consider this trial

Good fit: Ideal candidates include men aged 18 and older with confirmed prostate adenocarcinoma who are scheduled to begin hormonal therapy within eight weeks of an initial PSMA PET scan.

Not a fit: Patients who do not have prostate adenocarcinoma or are not planning to receive hormonal therapy within the specified timeframe may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved timing for PSMA PET imaging, enhancing treatment planning for prostate cancer patients.

How similar studies have performed: While this approach is novel in its specific focus on PSMA modulation in response to hormonal therapy, similar studies have shown promise in understanding tumor response to treatment.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Participant or legally authorized representative (LAR) must provide written informed consent before any study-specific procedures or interventions are performed.
* Participants must have confirmed prostate adenocarcinoma, histologically, or by combined imaging and biochemical markers.
* Age \>= 18 years. Given the nature of the disease in question, only men will be included. Members of all races and ethnic groups will be included.
* Participants must have sites of prostate cancer showing uptake on an initial PSMA PET scan.
* Participants are planned to receive hormonal therapy within eight weeks of the initial PSMA PET. The hormonal therapy agents include:

  * For CSPC: GnRH agonists, GnRH antagonists, first-generation antiandrogen (e.g. bicalutamide), or androgen receptor (AR)-targeted agent (e.g. Abiraterone, Enzalutamide, Apalutamide, Darolutamide)
  * For CRPC: this group of patients are typically on continuous ADT (GnRH agonists or antagonists), which will be continued, and the hormonal therapy they will be started on is an androgen receptor (AR)-targeted agent (e.g. Abiraterone, Enzalutamide, Apalutamide, Darolutamide)
* Life expectancy \> 3 months.
* Cohort 1: Castration resistant prostate cancer with rising PSA (confirmed by two PSA values at least 1 week apart), testosterone \< 50 ng/dL, on continuous ADT at least 4 months, no AR targeted agent in the prior 4 months.
* Cohort 2: Castration sensitive prostate cancer with no ADT or AR targeted agents use in the past 12 months, testosterone \>50 ng/dL

Exclusion Criteria:

* Uncontrolled serious infection.
* Intercurrent illness or condition that would limit compliance with study requirements.
* Participants who have undergone any cancer treatment other than the hormonal therapy (systemic or radiation therapy) or who have started any supplements or herbal medications intended to treat cancer between the baseline PSMA PET and PSMA PET at day 28.

Where this trial is running

Portland, Oregon

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.
Conditions Castration Resistant Prostate CancerCastration Sensitive Prostate CancerProstate Adenocarcinoma
Last reviewed 2026-06-15 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.