EValuation of radIOLigand Treatment in mEn With Metastatic Castration-resistant Prostate Cancer With [161Tb]Tb-PSMA-I&T

Inclusion Criteria

• •1. Patient has provided written informed consent.
• •2. Male patients must be 18 years of age or older at the time of written informed consent.
• •3. Histologically or cytologically confirmed adenocarcinoma of the prostate, OR unequivocal diagnosis of metastatic prostate cancer (i.e., involving bone or pelvic lymph nodes or para-aortic lymph nodes) with an elevated serum prostate specific antigen (PSA).
• •4. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2.
• •5. Patients must have had prior treatment with at least one line of taxane chemotherapy, unless medically unsuitable.
• •6. Patients must have had prior treatment with at least one second-generation androgen receptor (AR)-targeted agent (e.g., enzalutamide, abiraterone, apalutamide or darolutamide).
• •7. Patients must have progressive disease defined according to The Prostate Cancer Clinical Trials Working Group 3 (PCWG3) as any one of the following:
• •1. PSA progression - minimum of 2 rising PSA values from a baseline measurement with an interval of ≥ 1 week between each measurement
• •2. Soft tissue progression as per Response Evaluation Criteria in Solid Tumours version 1.1 (RECIST 1.1) criteria
• •3. Bone progression: ≥ 2 new lesions on bone scan
• •8. Prior surgical orchiectomy or chemical castration maintained on luteinizing hormone-releasing hormone (LHRH) analogue (agonist or antagonist).
• •9. Serum testosterone levels ≤ 1.75nmol/L (≤ 50ng/dL).
• •10. Significant prostate specific membrane antigen (PSMA) avidity on PSMA positron emission tomography (PET)/computed tomography (CT), defined as a minimum uptake of maximum standardised uptake value (SUVmax) 20 at a site of disease, and SUVmax \> 10 at sites of measurable soft tissue disease ≥ 15mm (unless subject to factors explaining a lower uptake, e.g. respiratory motion, reconstruction artefact).
• •11. Patients must have a life expectancy ≥ 6 months.
• •12. Patients must have adequate bone marrow, hepatic and renal function, defined as:
• •1. Haemoglobin ≥ 100g/L independent of transfusions (no red blood cell transfusion in last 4 weeks)
• •2. Absolute neutrophil count (ANC) ≥ 1.5 x 10\^9/L
• •3. Platelets ≥ 150 x 10\^9/L
• •4. Total bilirubin ≤ 1.5x upper limit of normal (ULN) except for patients with known Gilbert's syndrome, where this applies for the unconjugated bilirubin component
• •5. Aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 3x ULN if there is no evidence of liver metastasis or ≤ 5x ULN in the presence of liver metastases
• •6. Adequate renal function: patients must have a creatinine clearance estimated of ≥ 40mL/min using the Cockcroft Gault equation (Appendix 3)
• •13. Sexually active patients are willing to use medically acceptable forms of barrier contraception.
• •14. Willing and able to comply with all study requirements, including all treatments and the timing and nature of all required assessments.
• •15. At least 3 weeks since the completion of surgery or radiotherapy prior to registration.