A phase II, single arm two-phase, clinical study of individually adapted systemic radioligand therapy with 177Lu-PSMA I&T for patients with metastatic, castration-resistant prostate cancer

Condition studied

Prostate cancer

Eligibility

Primary endpoint

The primary endpoint of this study is biochemical Progression Free Survival (bPFS) from time of inclusion (baseline) until biochemical progression or death

Endpoint detail

Proportion of patients achieving a PSA decline of ≥50% from baseline (PSA50 response) at any time during treatment., Proportion of patients achieving a PSA decline of ≥90% from baseline (PSA90 response) at any time during treatment., Maximum percentage decline in PSA from baseline, Time from baseline to PSA progression, Duration of PSA response, defined as the time from the first documented PSA50 response until PSA progression., Molecular Response Rate (MRR): proportion of patients achieving Complete Molecular Response (CMR) or Partial Molecular Response (PMR) on 18F-DCFPyL PSMA PET/CT at Week 12, Week 24, End of Treatment, and End of Study, compared with baseline., Objective Response Rate (ORR): proportion of patients achieving Complete Response (CR) or Partial Response (PR) in measurable soft-tissue disease according to RECIST 1.1, assessed by contrast-enhanced CT at each scheduled imaging assessment, End of Treatment, and End of Study, compared with baseline, Disease Control Rate (DCR): proportion of patients achieving Complete Response (CR), Partial Response (PR), or Stable Disease (SD) according to RECIST 1.1., Time to Molecular Progression (TTMP): time from treatment initiation to Progressive Molecular Disease (PMD) on 18F-DCFPyL PSMA PET/CT, Radiographic Progression-Free Survival (rPFS): time from treatment initiation to radiological progression according to PSMA PET/CT, RECIST 1.1, or death from any cause, Changes in WHO/ECOG performance status before each treatment and at each follow up visit, compared to baseline, Changes in pain severity on a VAS scale from 1 to 10 before each treatment and at each follow up visit, compared to baseline, Time to first skeletal event defined as date of enrolment/baseline to date of first symptomatic bone fracture spinal cord compression, tumor-related orthopedic surgical intervention, or requirement for radiation therapy to relieve bone pain, whichever occurs first., Quality of life at each follow up visit compared to baseline, Adverse events/toxicity at each visit, Overall survival (OS) after treatment with 177Lu-PSMA I&T, Evaluate absorbed radiation dose to tumour and normal tissues using SPECT/CT after each treatment with study product, Experimental EP: Correlations between bPFS and uptake on PSMA-PET/CT and if possible FDG-PET/CT and it’s possible prognostic and predictive value, Experimental EP: Establishing predictive measures of tumour uptake levels on PET/CT (18F-PSMA and if possible FDG) after first, second and third treatment cycle, Experimental EP: Correlations between tumour uptake measuses from different modalities; 18F-PSMA-PET/CT (and FDG-PET/CT if possible) uptake rate as well as tumour absorbed radiation dose, Experimental EP: If possible, correlation between 18F-PSMA-PET/CT and FDG-PET/CT concerning both baseline charachteristics, and patient outcomes, Experimental EP: Establishing cut-offs of PSMA uptake below or above which 177Lu-PSMA therapy may be less, or more effective, and adapted dosing can be used