Flexible dosing of 177Lu-PSMA-617 for advanced prostate cancer treatment

A Phase 2 Randomized Trial in Patients With Metastatic Castration Resistant Prostate Cancer to Determine the Efficacy of a Flexible Dosing Schedule of Lu-PSMA Treatment up to 12 Cycles Including Potential Treatment Holiday Periods in Comparison to the Standard Fixed Dosing Schedule of Six Cycles Every Six Weeks (FLEX-MRT)

PHASE2 · Jonsson Comprehensive Cancer Center · NCT06216249

This study is testing if a flexible schedule for a prostate cancer treatment can help men with advanced cancer live longer and feel better compared to the usual fixed schedule.

Quick facts

PhasePHASE2
Study typeInterventional
Enrollment90 (estimated)
Ages18 Years and up
SexMale
SponsorJonsson Comprehensive Cancer Center (other)
Drugs / interventionschemotherapy
Locations1 site (Los Angeles, California)
Trial IDNCT06216249 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the effectiveness of a flexible dosing schedule of 177Lu-PSMA-617 in patients with metastatic castration-resistant prostate cancer (mCRPC) who have previously undergone chemotherapy and androgen receptor-targeted therapy. The study aims to determine if extending treatment cycles beyond the standard six can improve survival rates and quality of life while assessing safety and disease control. Participants will be randomized to receive either the flexible dosing schedule or the standard fixed schedule, with the potential for treatment holidays for those showing good responses. The trial will also explore the dosimetry of the treatment in organs and tumor lesions.

Who should consider this trial

Good fit: Ideal candidates are adults with histologically confirmed prostate cancer and at least one metastatic lesion who have received prior chemotherapy and androgen receptor-targeted therapy.

Not a fit: Patients who have not undergone prior chemotherapy or androgen receptor-targeted therapy may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could lead to improved survival and quality of life for patients with advanced prostate cancer.

How similar studies have performed: Previous studies have shown promise with similar approaches, but this flexible dosing strategy is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients must have prostate cancer proven by histopathology
* Patients must have ≥ 1 metastatic lesion by any imaging (CT, magnetic resonance imaging \[MRI\], bone scan, PET)
* Patients must have received at least one regimen of chemotherapy for mCRPC
* Patients must have received at least one androgen-receptor signaling inhibitors (ARSI)
* Patients must be eligible by PSMA PET VISION criteria. PSMA PET/CT must be performed within 8 weeks of planned first cycle of 177Lu-PSMA-617
* White blood cell (WBC) ≥ 2,500/ul
* Platelets (PLT) ≥ 100,000/ul
* Hemoglobin (Hb) ≥ 9.0 g/dl
* Absolute neutrophil count (ANC) ≥ 1,500 ul
* Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
* Patients must be adults ≥ 18 years of age
* Patients must have the ability to understand and sign an approved informed consent form (ICF)
* Patients must have the ability to understand and comply with all protocol requirements

Exclusion Criteria:

* Prior cycle of 177Lu-PSMA-617 therapy
* Less than 6 weeks between last myelosuppressive therapy (including docetaxel, cabazitaxel, strontium-89, samarium-153, rhenium-186, rhenium-188, radium-223, hemi-body irradiation) and first cycle of 177Lu-PSMA-617 therapy
* Glomerular filtration rate (GFR) \< 50 ml/min
* Urinary tract obstruction or marked hydronephrosis

Where this trial is running

Los Angeles, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Prostate Carcinoma, Stage IVB Prostate Cancer American Joint Committee on Cancer v8

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.