Response With Interim PSMA PET in Metastatic Castration-sensitive Prostate Cancer for Optimization of Adaptive Metastasis-directed Radiotherapy Delivery

NCT07674771 | Not Yet Recruiting Early Phase 1 DMC FDA Drug

• 1 other identifier: STU 20260850
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to characterize the reduction in PSMA-avid tumor volume and metastasis-directed radiotherapy treatment intensity facilitated by PET PSMA-response adapted SABR for poly-metastatic castration sensitive prostate cancer.

Conditions

Prostate Cancer; Castration Sensitive Prostate Cancer; Metastatic Prostate Cancer; Adaptive Radiotherapy

Keywords

prostate cancer; castration sensitive; stereotactic ablative radiotherapy; stereotactic body radiotherapy; metastatic prostate cancer; metastasis; adaptive radiotherapy

Outcome Measures

Primary Outcomes (2)

• Reduction in PSMA-positive TTV

  will be measured by the decrease in TTV (%) on a per-patient basis between the initial scan and post-SABR PSMA PET.

  1 YEAR

• Reduction in SABR treatment intensity

  Will be measured by the decrease in proportion of tumor lesions treated to initially prescribed 5 fractions (%) due specifically to complete metabolic response on interim PET PSMA after 3 fractions, as compared to initially planned lesions on a per patient basis.

  1 YEAR

Study Arms (1)

SINGLE ARM UNBLINDED SINGLE SITE PILOT

EXPERIMENTAL

Study will enroll patients with poly-metastatic hormone-sensitive prostate cancer, as identified by baseline PSMA PET imaging.Patients will undergo standard of care systemic therapy,including ADT \& androgen receptor signaling inhibitors intensification as clinically indicated,for up to 3 months before protocol radiotherapy.

Drug: Drug: 68-Ga PSMA11; Radiation: Adaptive stereotactic ablative radiotherapy (SABR); Drug: 68Ga-PSMA-11; Radiation: Adaptive stereotactive ablative radiotherapy (SABR)

Interventions

Drug: 68-Ga PSMA11 DRUG

0-3 months since initiation of ADT. Baseline PSMA PET imaging. 4-20 sites of metastasis by PSMA PET Will be injected/assessed in line with its FDA label. Other Name:

SINGLE ARM UNBLINDED SINGLE SITE PILOT

68Ga-PSMA-11 DRUG

Repeat PSMA PET imaging at 6 months post-ADT initiation. Radiation of primary allows. Will be injected/assessed in line with its FDA label.

SINGLE ARM UNBLINDED SINGLE SITE PILOT

Adaptive stereotactic ablative radiotherapy (SABR) RADIATION

Pre-plan 5 fraction SABR 35-40 Gy. SOC systemic therapy allows for ADT and ARSI intensification. Delivery of 3 pulses to all sites. Pulses delivered weekly.

SINGLE ARM UNBLINDED SINGLE SITE PILOT

Adaptive stereotactive ablative radiotherapy (SABR) RADIATION

Delivery of 2 additional pulses to all remaining PSMA PET visible sites

SINGLE ARM UNBLINDED SINGLE SITE PILOT

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: This study is enrolling men with 4-20 sites of metastasis from prostate cancer
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• History of pathologically confirmed prostate cancer.
• Age \>=18 years.
• Performance status ECOG 0-2.
• Staging 68Ga PMSA-11 PET/CT showing 4-20 sites of metastasis from prostate cancer within \<=90 days prior to registration. This scan ideally should be performed before initiation of androgen deprivation therapy (ADT).
• At the discretion of the treating investigator, it is believed that it is safe to treat all sites of disease using SABR.
• All men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of standard of care SABR and for a period of time of 6 months thereafter as per standard guidelines. Should a patient's partner become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.
• Ability to understand and the willingness to sign a written informed consent.
• Planned for standard systemic therapy for metastatic prostate cancer to include androgen deprivation therapy (ADT). Upfront Docetaxel should not be planned (See section 4.1.2).

You may not qualify if:

• Prior radiotherapy to any metastases currently targeted for therapy or overlapping regions.
• Patient with metastatic lesions involving the gastrointestinal tract, specifically, invading esophagus, stomach, or intestines will be excluded. Patients with ultra-central metastatic lesions defined as 1 cm from the trachea and main bronchi will be excluded.
• Serious medical co-morbidities precluding safe delivering of radiotherapy to poly-metastatic sites. This includes interstitial lung disease for patients undergoing SABR to thoracic sites and ulcerative colitis or Crohn's disease requiring systemic immunosuppressive therapy for patients undergoing SABR to GI sites.
• Subjects may not be receiving any other PSMA-directed investigational agents for the treatment of the cancer under study.
• History of allergic reactions to PMSA-11 68Ga imaging agent.
• Uncontrolled intercurrent illness or psychiatric illness/social situations that, in the opinion of the investigator, would limit compliance with study requirements.

Sponsors & Collaborators

• University of Texas Southwestern Medical Center: lead
• Varian, a Siemens Healthineers Company: collaborator
• Telix Pharmaceuticals (Innovations) Pty Ltd: collaborator

Study Sites (1)

University of Texas Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms; Neoplasm Metastasis

Interventions

gallium 68 PSMA-11

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases; Neoplastic Processes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• DANIEL YANG, MD

  University of Texas Southwestern Medical Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

SARAH NEUFELD, MS, MBA

CONTACT

214 645 8525; sarah.hardee@UTSouthwestern.edu

DANIEL YANG, MD

CONTACT

214 645 8525; daniel.yang@utsouthwestern.edu

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PRINCIPAL INVESTIGATOR

Model Details: 1 site pilot study with intent to characterize dynamic range of response by PET PSMA-11 68Ga characterization of poly-metastatic prostate cancer lesions \& safe delivery of comprehensive SABR using adaption based on PSMA metabolic response.Patients will undergo standard of care therapy, including ADT \& androgen receptor signaling inhibitors intensification as clinically indicated,for up to 3 months before protocol radiotherapy.The radiation oncologist will pre-plan SABR to a total of 35-40 Gy in 5 fractions. Trial will consist of initially delivering 3 qWeekly SABR "pulses" to all identified metastatic sites.First pulse should start within 60 (+/-30 days)of start of ADT. Following pulse 3,interim PSMA PET imaging to be repeated at 6 months from initiation of ADT(-30 days allowed)to evaluate response on a per lesion basis.In the absence of a complete response (CR) for a given lesion,2 additional qWeekly pulses may be delivered to these sites within 60 days from interim PSMA PET.

Study Record Dates

• First Submitted: June 24, 2026
• First Posted: June 30, 2026
• Study Start: July 15, 2026
• Primary Completion (Estimated): June 15, 2029
• Study Completion (Estimated): June 15, 2029
• Last Updated: July 23, 2026

Record last verified: 2026-06

Locations

US (1)