Phase I Study of [225Ac]Ac-ETN029 in Patients With Advanced DLL3-expressing Solid Tumors

This is a Phase I study testing a new radioactive cancer drug called [225Ac]Ac-ETN029, which targets a protein called DLL3 found on certain cancer cells. It is being tested in patients with advanced small-cell lung cancer or other rare neuroendocrine tumors. **You may be eligible if...** - You are 18 years or older - You have advanced small-cell lung cancer (SCLC) that progressed after at least one prior treatment including platinum-based chemotherapy - Or you have a large-cell neuroendocrine cancer of the lung, neuroendocrine prostate cancer, or a gastrointestinal/pancreatic high-grade neuroendocrine carcinoma that has progressed on prior treatment - Your cancer expresses the DLL3 protein (for expansion groups) - You have measurable disease on imaging **You may NOT be eligible if...** - Your cancer has not been previously treated - You do not have the DLL3 protein marker on your tumor (for expansion groups) - You are pregnant or breastfeeding - Your organ function does not meet required levels Talk to your doctor to see if this trial is right for you.