Patients With Metastasized Prostate Cancer Whose Prostate-specific Antigen-level (PSA) Remains >0,2 ng/ml After Six Months of Dual Antihormonal Therapy Will Receive Radiotherapy to the Prostate and Radiotherapy to Refractory Metastases

NCT07644754 | Not Yet Recruiting

• 2 other identifiers: 430/2025BO1DRKS00038018
• Study Type: interventional
• Target: 27
• Locations: 0 countries
• Sites: N/A

Brief Summary

The goal of this clinical trial is to learn if radiotherapy to the prostate and PET-positive (positron emission tomography) metastasis will lead to radiological response on PSMA-PET (prostate specific membrane antigen-PET). Patients who receive combined androgen deprivation therapy for de novo metastasized prostate cancer and show an incomplete PSA-response (\>0,2 ng/ml after six months) and exhibit at least four bone metastases on PET-imaging at this time point (without metastases to organs) can take part in this study. The main questions it aims to answer are:

• Does radiotherapy to the prostate and PET-positive metastases lead to a radiological response one year after radiotherapy? Researchers will analyze PET-imaging prior to radiotherapy to the prostate and metastases and one yeare thereafter. Participants will:
• Continue taking combined androgen-deprivation therapy
• Receive a total of three PSMA-PET/CT scans
• Receive radiotherapy to the prostate and PET-positive metastases
• Visit the clinic every three months for 36 months
• Complete quality of life questionnaires at every visit

Conditions

Prostate Cancer; Prostate Cancer Metastatic Disease; Prostate Cancer Metastatic to Bone

Keywords

mHSPC; insufficient PSA-response to dual antihormonal treatment; local therapy; radiotherapy

Outcome Measures

Primary Outcomes (1)

• Radiological Progression-Free Survival

  Radiological Progression-Free Survival as determined on PSMA-PET/CT according to RECIP criteria, defined as 30% response in PSA-volume

  12 months after radiotherapy of metastases

Secondary Outcomes (9)

• Lesion-specific response on imaging

  12 months after radiotherapy to metastases

• Prostate specific antigen (PSA)

  up to 36 months after radiotherapy to the prostate

• Objective response rate

  12 months after radiotherapy to metastases

• Time to next systemic therapy

  up to 36 months after radiotherapy to the prostate

• Overall survival

  up to 36 months after radiotherapy to the prostate

Other Outcomes (11)

• Quality of life questionnaires

  up to 36 months after radiotherapy of the prostate

• Organ-specific side effects

  up to 36 months after radiotherapy of the prostate

• Organ function

  up to 36 months after radiotherapy of the prostate

Study Arms (1)

Radiotherapy to the prostate and PSMA-PET/CT guided radiotherapy of refractory metastases

EXPERIMENTAL

Radiotherapy to the prostate and refractory metastases on PSMA-PET/CT

Radiation: Radiotherapy to the prostate and to PSMA-PET positive metastases

Interventions

Radiotherapy to the prostate and to PSMA-PET positive metastases RADIATION

Patients will receive radiotherapy to the prostate and to PSMA-PET postivie Metastases

Radiotherapy to the prostate and PSMA-PET/CT guided radiotherapy of refractory metastases

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Prostate adenocarcinoma
• de novo metastasized prostate cancer (at least 4 osseous metastases +/- lymphonodal metastases)
• first-line combined antihormonal therapy (ADT + ARPI) for six months
• PSA \> 0,2 ng/ml after six months of combined ADT/ARPI therapy
• multimetastasized disease stage without visceral metastases on imaging at first diagnosis (PET, CT, or bone scan)
• \<16 osseous/lymphnodal metastases on response assessment imaging (PSMA-PET/CT) after six months of combined antihormonal therapy

You may not qualify if:

• neuroendocrine histology
• visceral metastases (M1c)
• prior radiotherapy to the pelvis
• PSA \< 0,2 ng/ml after 6 months of combined antihormonal therapy
• prior prostatectomy
• contraindication against PSMA-PET/CT and/or radiotherapy to the prostate/metastases
• HIFU or TUR-P within 6 months of study treatment
• relevant GU/GI condition (active fistula or other)
• known tumor predisposition syndrome

Sponsors & Collaborators

• University Hospital Tuebingen: lead
• Ludwig-Maximilians - University of Munich: collaborator
• University Hospital Freiburg: collaborator
• University Hospital Dresden: collaborator
• Uniklinikum Giessen und Marburg: collaborator
• University Hospital Augsburg: collaborator

MeSH Terms

Conditions

Prostatic Neoplasms

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Study Officials

• Elgin Hoffmann, MD

  Department of Radiation Oncology, University Hospital Tübingen

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Elgin Hoffmann, MD, Dr. med.

CONTACT

4970712982165; ROinfo@med.uni-tuebingen.de

Maximilian Niyazi, MD, Prof. Dr. Dipl.-Phys.

CONTACT

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 1, 2026
• First Posted: June 12, 2026
• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): February 1, 2031
• Last Updated: June 12, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share