A Study of 177Lu-DTPA-SC16.56 in People With Neuroendocrine Carcinomas of the Lung and Prostate

Inclusion Criteria: * Subjects with histologically proven progressive metastatic high-grade neuroendocrine carcinomas of the lung (small-cell lung cancer) and prostate (neuroendocrine prostate cancer) that has relapsed following at least 1 line of standard chemotherapy i. Prostate cancer patients will be defined by either of the following criteria: ii. The presence of chromogranin staining on tissue iii. At least two of the pathogenic mutations of PTEN, RB1, or p53 iv. Disease exclusively involving the viscera v. Disease in which the PSA is \<10 but the number of bone lesions is \>20 vi. Histologic evidence of small cell carcinoma or other stains consistent with neuroendocrine disease (on the primary disease or metastases) vii. DLL3 positivity on previously available tissue specimens * Ability to understand and willingness to sign a written informed consent document * Aged 18 years or older at the time of signing consent * Progression of disease defined by one of the following occurring within 3 months of study entry: i. At least a 20% increase in radiologically or clinically measurable disease; ii. Appearance of any new lesion; iii. For prostate cancer patients progression criteria will be per PCWG3: iv. Either v. A rising PSA over a sequence of at least 1-week intervals OR i. An increase in soft tissue disease to qualify for disease progression by RECIST 1.1 OR ii. Two new bone lesions by bone scintigraphy Patients with metastatic disease by virtue of disease exclusive…