Exploratory PK and Imaging Study of PSMA-Targeted Trillium Compounds and PTI-122 in Metastatic Prostate Cancer

Inclusion Criteria:

• Adult males with metastatic prostate cancer
• ECOG performance score 0-2
• Stable androgen deprivation or other hormone therapy (30 days) or therapy planned butnot yet initiated
• PSMA PET scan between 3 and 28 days prior to radiotracer injection with at least 2PSMA positive lesions and either:

1. One soft tissue lesion measuring ≥ 15 mm in the longest diameter with SUVmaxlesion ≥ SUVmean normal liver, OR
2. Two bone lesions measuring ≥ 15 mm in the longest diameter with SUVmax lesion ≥ 2x SUVmax normal liver

• Able to understand and adhere to study requirements, and voluntarily give informedconsent

Exclusion Criteria:

• No other malignancy undergoing treatment
• No PSMA-targeted therapy ongoing
• Inability or unwillingness to undergo SPECT/CT imaging
• Serum creatinine > 1.5 mg/dL or creatinine clearance ≤50 mL/min by Cockcroft-Gaultestimation
• Concurrent participation in the active treatment phase of another clinical trial ofinvestigational medicinal product(s)
• Significant intercurrent illness, treatment-related toxicity, or psychiatricillness/social situation that could place the subject at undue risk during studyparticipation, significantly alter study outcomes, or affect subject compliance withstudy requirements for dosing and evaluation, as determined by the investigator