**Study Overview:** This research is about testing a new medicine called BL-M07D1 to see if it is safe and works well for adults with certain types of cancer. The study focuses on cancers that have a protein called HER2, which can make cancer grow faster. These cancers include breast, lung, and others. The study is in its early phase, called Phase 1, where scientists test the medicine on a small group of people to check how safe it is and how it acts in the body. **Key Points:** - **Study Duration and Visits:** Participants receive the treatment on the first day of each 21-day cycle. The study is divided into three parts, each testing different doses. - **Eligibility:** To join, you must be 18 or older, have a life expectancy of at least 3 months, and have a specific type of cancer that didn't respond to other treatments. - **Risks and Benefits:** While this study may not directly benefit you, it helps researchers understand if the medicine is safe and effective for future patients. There are risks, including possible side effects from the treatment. If you meet the criteria and are interested, you might consider joining to help advance cancer research.