A Study of FZ-AD005 in Patients With Advanced Solid Tumors

This study is testing a new drug called FZ-AD005 in people with advanced solid tumors, particularly small cell lung cancer (SCLC) or large cell neuroendocrine carcinoma (LCNEC). The goal is to assess the drug's safety and find the best dose. **You may be eligible if...** - You are between 18 and 75 years old - You have been diagnosed with an advanced solid tumor — especially SCLC or LCNEC - You have measurable tumors on scans - You are in good overall health (ECOG 0–1) - You have a life expectancy of at least 3 months - You can provide a tumor tissue sample **You may NOT be eligible if...** - You have previously received any anti-DLL3 antibody treatment - You have had another cancer in the past 5 years - You have active brain metastases (cancer that has spread to the brain) - You are pregnant or breastfeeding - You have had major surgery or high-dose steroids recently - You have a significant psychiatric history Talk to your doctor to see if this trial is right for you.