A Dosimetry Study of Lutetium (177Lu) rhPSMA-10.1 and Lutetium (177Lu) Vipivotide Tetraxetan (Pluvicto®) in Patients With Non-curative Metastatic Prostate Cancer

Inclusion Criteria:

* Male patient aged ≥60 years old at Visit 1 (Screening).
* Patient has non-curative PSMA-positive prostate cancer that has spread outside of the prostate gland and is undergoing or being planned for radioligand therapy.
* At least 1 PSMA-positive lesion that can be outlined on PET or CT and ≥1 cm in the short axis measured on either modality, for the purpose of dosimetry.
* Adequate normal organ function as demonstrated by:

  * Absolute neutrophil count ≥1.5 × 109/L
  * Platelets ≥100 × 109/L
  * Haemoglobin ≥9 g/dL
  * Total bilirubin \<2 × the institutional upper limit of normal (ULN). For patients with known Gilbert's Syndrome, ≤3 × ULN is permitted.
  * Alanine aminotransferase (ALT) or aspartate transaminase (AST) ≤3.0 × ULN or ≤5.0 × ULN for patients with liver metastases.
  * Estimated glomerular filtration rate (using Chronic Kidney Disease Epidemiology Collaboration Creatinine Equation \[2009\]) \>50 mL/min.
* Willing to provide signed and dated written informed consent form (ICF) prior to any study specific procedures
* Male patients must agree not to father children or donate sperm during the study and for at least 14 weeks after the last study treatment.

Exclusion Criteria:

* Known hypersensitivity to lutetium (177Lu) rhPSMA 10.1 or lutetium (177Lu) vipivotide tetraxetan, or any of the constituents.
* Previous treatment with any radiopharmaceutical therapy in the 42 days or 5 half-lives prior to Visit 1 (Screening).
* Any significant metallic implants or objects, which may in the opinion of the investigator, affect image quality and/or dosimetry calculations.
* Severe claustrophobia, inability to lie flat or fit into the scanner, or any other inability to tolerate the SPECT/CT scan protocol
* Any change to prostate cancer medication or new prostate cancer therapy, prostate cancer surgical procedure within 42 days prior to screening or during the study.
* Any medical or psychiatric condition, including rapidly progressive prostate cancer, that in the investigator's judgment, makes the patient unsuitable for the study
* Participation in other studies involving other IMPs within 42 days or 5 half lives (whichever is longer) prior to Visit 1 (Screening) and/or during study participation