Liquid Biopsy Under PSMA Radioligand Therapy

Recruiting

• Conditions: Prostate Cancer Metastatic Castration-Resistant; Prostate Cancer

• Registration Number: NCT07118436
• Lead Sponsor: Wuerzburg University Hospital

Brief Summary

Prostate cancer is the second most common cause of cancer death in men worldwide. After exhausting guideline-compliant therapies or in accordance with the approval of 177Lu-PSMA-617 (Pluvicto®), patients with metastatic castration-resistant prostate cancer (mCRPC) can be offered radioligand therapy (RLT) that targets the prostate-specific membrane antigen (PSMA). Despite an initially high response rate to PSMA-RLT, the disease often progresses rapidly again. The underlying mechanisms are still poorly understood.

Liquid biopsy (LBx) involves the collection and analysis of body fluids, particularly blood. Its major advantage compared to a tissue sample is its non-invasive nature, allowing for multiple samplings, as well as the examination of more than just a single punctured lesion. Among other things, circulating tumor DNA (ctDNA) can be detected in the blood.

The aim of this study is to apply LBx before, during, and after PSMA-RLT in patients with mCRPC to determine prognostic factors before therapy and to assess the value of LBx in evaluating treatment response. Furthermore, LBx will be used to gather information on the course of potential tumor heterogeneities and to determine resistance mechanisms against PSMA-RLT.

To this end, patients receiving PSMA-RLT will be enrolled in the study at three sites (University Hospital Wuerzburg, University Hospital Augsburg, Klinikum rechts der Isar Munich). The evaluation of clinical and imaging parameters will be carried out centrally at the University Hospital Wuerzburg, while the analysis of LBx will be performed at the University Hospital Augsburg.

Detailed Description

Not available

Study Timeline

• Study Start: 2024-09-01
• Study First Submitted: 2025-07-28
• Status Verified: 2025-08
• Study First Submitted QC: 2025-08-08
• Last Update Submitted: 2025-08-08
• Study First Posted: 2025-08-12
• Last Update Posted: 2025-08-12
• Primary Completion: 2026-12
• Study Completion: 2028-08-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Male
• Target Recruitment: 100

Inclusion Criteria

• Patients with mCRPC eligble for PSMA RLT
• In-lable use for PSMA RLT
• PSMA PET/CT not older than 8 weeks prior to first cycle of PSMA RLT
• One previous line of antiandrogen receptor pathway treatment and one previous line of taxan based therapy
• Age ≥ 18 years
• Written informed consent
• Sufficient knowledge of the German language or presence of a translator

Exclusion Criteria

• Unwilling to adhere to study procedures
• Missing interdisciplinary tumor conference advise for PSMA RLT

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Prognostic value of LBx (precisely ctDNA) before PSMA RLT	16-18 weeks	identification of responders (partial response and stable disease)/non-responders (progressive disease) after 2 cycles of PSMA RLT, time-to-event analysis that could provide insights into overall survival or progression-free survival based on ctDNA level
Comparison of response assessment using LBx with biochemical response (PSA) after 2 cycles of PSMA RLT	16-18 weeks
Comparison of response assessment using LBx with imaging-based response (PSMA PET/CT) after 2 cycles of PSMA RLT	16-18 weeks

Trial Locations

Locations (2)

University hospital Wuerzburg - Department of Nuclear Medicine; 🇩🇪 Wuerzburg, Germany

TUM Klinikum rechts der Isar - Department of Nuclear medicine; 🇩🇪 München, Germany