A Study of BL-M17D1 in Patients With Locally Advanced or Metastatic HER2 Positive/Negative Breast Cancer and Other Solid Tumors

This study tests a new cancer drug called BL-M17D1, which is an antibody-drug conjugate — a targeted therapy that delivers chemotherapy directly to cancer cells. It is being tested in patients with advanced or metastatic breast cancer (both HER2-positive and HER2-negative) and other solid tumors that have not responded to prior treatments. **You may be eligible if...** - You are 18–75 years old (or 18 and older for later stages of the study) - You have locally advanced or metastatic breast cancer or another solid tumor - You are in good general health and able to perform daily activities - Your organs (heart, liver, kidneys) are functioning adequately - You are not pregnant and willing to use contraception **You may NOT be eligible if...** - You have received chemotherapy or targeted therapy in the last 4 weeks - You have a history of severe heart disease - You have active brain metastases - You are pregnant or breastfeeding - You have uncontrolled infections or serious medical conditions Talk to your doctor to see if this trial is right for you.