Based on data from the Interim Analysis, the study will not adequately inform the clinical development programme for Lutetium (177Lu) rhPSMA-10.1 injection in the way that the study was intended. There are no concerns regarding participant safety.

A randomised, multi-centre, intra-patient imaging and dosimetry crossover 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