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

NCT07210086 | Recruiting Phase 2 DMC FDA Drug

• 3 other identifiers: 25339P30CA033572NCI-2025-07236
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief 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.

Conditions

Prostate Cancer

Keywords

Prostate Cancer

Outcome Measures

Primary Outcomes (1)

• Early PD on PSMA-PET prior to PSA-progression

  Estimate percentage of patients whose PSMA\_PET shows progressing disease (either on new sites or previously irradiated sites) prior to PSA progression

  Up to 5 years

Secondary Outcomes (2)

• Describe the PET response to lesions and its relationship to PSA changes

  Up to 5 years.

• Characterize the changes in ctDNA levels

  Up to 5 years.

Study Arms (3)

De novo oligometastatic disease treated with ADT+ARSI+ablative intent RT

OTHER

De novo oligometastatic disease treated with ADT+ARSI+ablative intent RT and who have \<=5 extrapelvic lesions detected on a baseline PSMA-PET and have rising PSA.

Drug: ADT; Drug: ARSI

Recurrent disease with oligometastatic disease treated with ADT+ablative intent RT

OTHER

Recurrent disease with oligometastatic disease treated with ADT+ablative intent RT and who have \<=5 extrapelvic lesions detected on a baseline PSMA-PET and have rising PSA.

Drug: ADT

Recurrent prostate ca with oligometastatic disease who decline ADT/ARSI

OTHER

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.

Other: No ADT/ARSI -decline

Interventions

ADT DRUG

Androgen Deprivation Therapy

De novo oligometastatic disease treated with ADT+ARSI+ablative intent RT; Recurrent disease with oligometastatic disease treated with ADT+ablative intent RT

ARSI DRUG

Androgen Receptor Signaling Inhibitor

De novo oligometastatic disease treated with ADT+ARSI+ablative intent RT

No ADT/ARSI -decline OTHER

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.

Recurrent prostate ca with oligometastatic disease who decline ADT/ARSI

Eligibility Criteria

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

You may qualify if:

• Documented informed consent of the participant or legally authorized representative.
• Age: ≥ 18 years
• KPS ≥ 70 or ECOG 0-1 (Appendix A)
• Biopsy-confirmed diagnosis of castration-sensitive prostate adenocarcinoma, as defined by rising PSA in setting of T\>100
• Clinical diagnosis of de novo oligometastatic or oligoprogressive disease, as defined by one the following:
• De novo oligometastatic: newly diagnosed prostate cancer AND ≤ five metastatic sites outside of the pelvis (Metastatic sites may not be brain or liver.) OR Hormone Sensitive Oligoprogressive: history of prior local therapy for prostate cancer AND ≤ five progressing metastatic sites outside of the pelvis (Metastatic sites may not be brain or liver.) AND Hormone sensitive defined as clinical progression in absence of castration (T\>100)
• Measurable disease by PERCIST v1.0
• Eligible to receive ablative-intent radiation therapy (biologically effective dose \[BED\] \>100, α/β ratio:2) directed to all sites of metastatic disease.
• Primary site of disease (Prostate +/- Seminal Vesicles) is controlled or will receive ablative intent treatment as a part of this treatment course.
• Baseline flotufolastat F18 PET imaging, if obtained as part of standard of care, is acceptable provided it was performed prior to the initiation of radiation therapy.
• Agreement by females and males of childbearing potential\* to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 30 days after the last dose of protocol therapy. \* Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for \> 1 year (women only).
• Any patient planning to receive lifelong continuous or intermittent ADT
• For the current treatment course, patient must not have received more than 3 months of neoadjuvant ADT prior to consent.
• Any contraindication to receiving flotufolastat F 18.
• Diagnosis of polymetastatic (newly diagnosed prostate cancer and more than five metastatic sites outside of the pelvis or metastatic sites in brain or liver.)

Sponsors & Collaborators

• City of Hope Medical Center: lead
• National Cancer Institute (NCI): collaborator

Study Sites (1)

City of Hope Medical Center

Duarte, California, 91010, United States

RECRUITING

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

• Rose Li, MD, PhD

  City of Hope Medical Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Rose Li, MD, PhD

CONTACT

6263598111; yunroseli@coh.org

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 29, 2025
• First Posted: October 7, 2025
• Study Start: November 26, 2025
• Primary Completion (Estimated): May 13, 2028
• Study Completion (Estimated): May 13, 2028
• Last Updated: January 28, 2026

Record last verified: 2026-01

Locations

US (1)