Androgen Receptor Signaling and Prostate-Specific Membrane Antigen Expression

February 11, 2026 updated by: David J. Einstein, Beth Israel Deaconess Medical Center

Understanding the Interaction Between Androgen Receptor Signaling and Prostate-Specific Membrane Antigen Expression

The goal of this research study is to determine whether hormonal therapies used early in the course of prostate cancer could increase the amount of Prostate-Specific Membrane Antigen (PSMA) as detected by PET/CT scans for participants with recurrent prostate cancer. This study will measure PSMA levels using standard PET/CT scans and participants will receive standard-of-care androgen receptor antagonist monotherapy.

The names of the treatment interventions involved in this study are:

  • Androgen receptor antagonist monotherapy.
  • PSMA PET/CT scan

It is expected that about 15 people will take part in this research study.

Participation in this research study is expected to last about 4 weeks.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Detailed Description

This research study is a pilot study, and it is the first time investigators are directly examining the effect of standard androgen receptor antagonists on Prostate-Specific Membrane Antigen (PSMA) expression for participants with recurrent, asymptomatic, metastatic hormone-sensitive prostate cancer (mHSPC). This study will measure PSMA levels using standard PET/CT scans and participants will receive standard-of-care androgen receptor antagonist monotherapy.

The research study procedures include screening for eligibility, study imaging and evaluations, blood collections, and follow up visits.

The names of the treatment interventions involved in this study are:

  • Androgen receptor antagonist monotherapy.
  • PSMA PET/CT scan

The U.S. Food and Drug Administration (FDA) has approved apalutamide, darolutamide, and enzalutamide for the treatment of prostate cancer.

It is expected that about 15 people will take part in this research study.

Participation in this research study is expected to last about 4 weeks.

Funding for this research study is provided by a philanthropic gift.

Study Type

Interventional

Enrollment (Actual)

9

Phase

  • Early Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Massachusetts
      • Boston, Massachusetts, United States, 02215
        • Beth Israel Deaconess Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

40 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients age 40 or higher with prostate cancer that has been previously treated with primary definitive local therapies (prostatectomy with or without salvage radiation, or primary prostate radiation) and subsequently experiencing rising PSA meeting criteria for biochemical failure (PSA >0.2 ng/dL x2 following prostatectomy, or PSA > 2 + nadir value following primary radiation).
  • PSMA PET/CT (Ga68, piflutolastat F-18, or other FDA-approved tracer) during time of biochemical recurrence, and within 6 weeks of registration, showing at least one lesion suspicious for recurrent prostate cancer based on size and/or SUV.
  • Testosterone >100 ng/dL within 6 months prior to enrollment with no intervening hormonal therapies.
  • Assigned by treating physician to receive standard-of-care AR antagonist monotherapy, using FDA-approved apalutamide, darolutamide, or enzalutamide.

Exclusion Criteria:

  • High disease burden, significant symptoms of disease, or other clinical situation requiring medical/surgical castration and/or docetaxel during the time of the study.
  • Not suitable for AR antagonist therapy (e.g. inability to swallow pills, poor adherence, advanced liver disease, prohibitive co-payment without available patient assistance funding, contraindicated drug-drug interaction).
  • Older-generation AR antagonists (e.g. bicalutamide) are not allowed on study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Androgen Receptor Antagonist Monotherapy
  • Participants will receive pre-determined doses of apalutamide, darolutamide, or enzalutamide per standard care.
  • Participants will undergo Prostate-Specific Membrane Antigen (PSMA) PET/CT scans at weeks 1 and 4.
Drug: Apalutamide [Erleada], darolutamide [Nubeqa], or enzalutamide [Xtandi]
per standard care
Diagnostic test: Prostate-Specific Membrane Antigen (PSMA) PET/CT Scan
Per standard care

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proportion of Participants with New Lesions (Flare)
Time Frame: week 1
Defined as the percentage of patients having the appearance of at least one new suspicious lesion or increase in SUV max relative to each individual's baseline.
week 1
Proportion of Participants with New Lesions (Flare)
Time Frame: week 4
Defined as the percentage of patients having the appearance of at least one new suspicious lesion or increase in SUV max relative to each individual's baseline.
week 4

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Changes in tumor size
Time Frame: week 1
Defined as maximum diameter of lesions for up to 5 target lesions. Standardized Uptake Value Max and Mean.
week 1
Changes in tumor size
Time Frame: week 4
Defined as maximum diameter of lesions for up to 5 target lesions. Standardized Uptake Value Max and Mean.
week 4
Changes in tumor SUV
Time Frame: week 1
For up to 5 target lesions. Standardized Uptake Value Max and Mean.
week 1
Changes in tumor SUV
Time Frame: week 4
For up to 5 target lesions. Standardized Uptake Value Max and Mean.
week 4
Changes in serum PSA
Time Frame: week 1
week 1
Changes in serum PSA
Time Frame: week 4
week 4

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Beth Israel Deaconess Medical Center

Collaborators

Dana-Farber Cancer Institute

Investigators

  • Principal Investigator: David Einstein, MD, Beth Israel Deaconess Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 19, 2023

Primary Completion (Actual)

September 18, 2025

Study Completion (Estimated)

September 1, 2026

Study Registration Dates

First Submitted

December 19, 2022

First Submitted That Met QC Criteria

January 4, 2023

First Posted (Actual)

January 13, 2023

Study Record Updates

Last Update Posted (Actual)

February 13, 2026

Last Update Submitted That Met QC Criteria

February 11, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 22-441

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

The Dana-Farber / Harvard Cancer Center encourages and supports the responsible and ethical sharing of data from clinical trials. De-identified participant data from the final research dataset used in the published manuscript may only be shared under the terms of a Data Use Agreement. Requests may be directed to: [contact information for Sponsor Investigator or designee]. The protocol and statistical analysis plan will be made available on Clinicaltrials.gov only as required by federal regulation or as a condition of awards and agreements supporting the research.

IPD Sharing Time Frame

Data can be shared no earlier than 1 year following the date of publication

IPD Sharing Access Criteria

Contact the Beth Israel Deaconess Medical Center Technology Ventures Office at tvo@bidmc.harvard.edu

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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