A Study of BL-B01D1 in Patients With Locally Advanced or Metastatic Gastrointestinal Tumor and Other Solid Tumor

This study is testing a new antibody-drug combination called BL-B01D1 in people with advanced solid tumors — including triple-negative breast cancer — that have not responded to standard treatments. The drug targets a protein on the surface of cancer cells called TROP2. **You may be eligible if...** - You are between 18 and 75 years old (for Phase Ia) or 18 or older (for Phase Ib) - You have been diagnosed with locally advanced or metastatic triple-negative breast cancer or another solid tumor - Your cancer has stopped responding to standard therapies or you are not eligible for them - You are willing to provide a tumor tissue sample - You are expected to survive at least 3 months **You may NOT be eligible if...** - You have active brain metastases that are untreated or unstable - You have uncontrolled infections or serious heart or lung conditions - You are pregnant or breastfeeding - You have had recent major surgery or radiotherapy Talk to your doctor to see if this trial is right for you.