NCT06216249RecruitingPhase 2
Phase 2 Randomized Trial of Flexible Dosing Schedule of 177Lu-PSMA-617 for the Treatment of Metastatic Castration-Resistant Prostate Cancer (FLEX-MRT)
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)
Source: ClinicalTrials.gov · Last updated 10 Mar 2026
Brief summary (registry, in English)
In advanced metastatic castration resistant prostate cancer (mCRPC) progressing after chemotherapy and androgen receptor (AR)-targeted therapy 177Lu-PSMA-617 is an effective treatment. 177Lu-PSMA-617 RLT is administered with a fixed schedule: 6 treatment cycles, administered every 6 weeks. However, the optimum number of cycles of 177Lu-PSMA in patients who show good response remains unknown. Some patients may benefit from more than 6 cycles of therapy. Additionally, some patients experience a complete or almost complete response before the last cycle. It is unclear whether these patients benefit from the subsequent remaining treatment cycle(s). A treatment holiday period would spare these patients some exposure to the therapy agent and avoid potentially unnecessary toxicity when treatment efficacy is already maximal and additional treatment effect cannot be expected. This randomized phase 2 study compares a group of patients treated with LuPSMA on a flexible and extended dosing schedule including "treatment holiday" periods (investigational arm, up to 12 cycles, as described below) to a control group treated with a fixed dosing schedule of 6 treatments cycles maximum administered every 6 weeks. The flexible dosing schedule in the investigational arm will be based on single photon emission computed tomography (SPECT)/computed tomography (CT) response assessments obtained 24h after injection of LuPSMA therapy cycle. The response assessment during treatment holiday period will be based on positron emission tomography/computed tomography (PET/CT) every 12 weeks. Single-time point SPECT/CT dosimetry protocol at every cycle will be performed and will allow to determine the number of cycles that subjects may receive under the study without exceeding the kidney dose threshold.
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 2
- Study type
- Interventional
- Enrollment
- 90 (estimated)
- First submitted
- 30 Nov 2023
- Start date
- 1 Aug 2024
- Primary completion date
- 31 Dec 2027
- Lead sponsor
- Jonsson Comprehensive Cancer Center
- Diseases
- Prostate cancer
- NCT number
- NCT06216249
What you commit to
- Study type: Interventional · Phase 2
- Planned participants: 90
- From 1 Aug 2024 to the primary completion date, 31 Dec 2027
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- 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
Lab values
- Glomerular filtration rate (GFR) \< 50 ml/min
Other
- Urinary tract obstruction or marked hydronephrosis
Who the study is looking for
- 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
Age in the registry: 18 years to - · Sex: Male · Does not accept healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| UCLA / Jonsson Comprehensive Cancer Center Coordinator of this site? Confirm its status | Los Angeles | United States | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.