NCT07210086

Phase II Non-Randomized Study Evaluating POSLUMA-PSMA PET Response After Oligo- Metastatic/Progressive-directed Treatment With Radiotherapy (PROMPT-R)

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 50 (estimated)
• Sponsor: City of Hope Medical Center · Academic / Other
• Sex: Male
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study aims to evaluate the role of PSMA-PET and circulating tumor DNA (ctDNA) in monitoring prostate cancer progression and response to radiotherapy (RT). Specifically, it investigates how often early progression is detected on PSMA-PET before PSA rise, examines PET responses of lesions treated with RT at 6 and 12 months and their correlation with PSA changes and later progression, examines ctDNA changes following ablative-intent RT to metastatic sites, and explores the relationship between PSMA-PET radiological findings and ctDNA dynamics.

Detailed description

Primary Objective: \* Identify the frequency of early progressive disease on PSMA-PET prior to PSA progression. Secondary Objectives: * Describe the PET response to lesions given RT at 6 months (and 12 month if applicable), and its relationship to PSA changes, and to later progressive disease both on PET and with PSA progression for each cohort * Characterize the changes in ctDNA levels after ablative-intent RT to metastatic sites. * Describe the radiological changes from PSMA-PET and its relationship with ctDNA.

Conditions

• Prostate Cancer

Interventions

Type	Name	Description
DRUG	ADT	Androgen Deprivation Therapy
DRUG	ARSI	Androgen Receptor Signaling Inhibitor
OTHER	No ADT/ARSI -decline	Recurrent prostate cancer with oligometastatic disease who decline ADT/ARSI and are treated with ablative intent RT alone and who have \<=5 extrapelvic lesions detected on a baseline PSMA-PET and have rising PSA.

Timeline

• Start date: 2025-11-26
• Primary completion: 2028-05-13
• Completion: 2028-05-13
• First posted: 2025-10-07
• Last updated: 2026-01-28

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study