Testing the Safety of the Anti-cancer Drug, Sn-117m-DTPA, for Advanced Cancers That Have Spread to Bones

This phase I trial tests the safety, side effects and best dose of tin (Sn)-177m-diethylenetriaminepentaacetic acid (DTPA) and how well it works in treating prostate, breast or non-small cell lung cancer that has spread from where it first started (primary site) to the bones (bone metastases). Sn-117m-DTPA was originally tested in tumors that had spread to the bones to help reduce bone pain. The drug has been improved and is designed to send low-level radiation to tumors in the bone while being gentler on the bone marrow, where blood cells are made. Sn-117m-DTPA may be safe and tolerable, and may slow down or shrink tumors in patients with metastatic prostate, breast, or non-small cell lung cancer that has spread to the bones.

NCT Number	NCT06982222
Lead Sponsor	National Cancer Institute (NCI)
Conditions	Anatomic Stage IV Breast Cancer AJCC v8, Metastatic Breast Carcinoma, Metastatic Lung Non-Small Cell Carcinoma, Metastatic Malignant Neoplasm in the Bone, Metastatic Prostate Adenocarcinoma, Stage IV Lung Cancer AJCC v8, Stage IVB Prostate Cancer AJCC v8
Enrollment	24 participants
Start Date	2026-10-01
Primary Completion	2027-02-12 (estimated)
Study Completion	2027-02-12 (estimated)
Updated on ClinicalTrials.gov	2026-05-13