This study is testing a new drug called TQB2930 for people with breast cancer that has returned or spread (metastatic). The study is in two parts. Phase Ib looks at how much of the drug people can safely take. Phase II tests the drug in combination with another cancer drug called docetaxel.

Eligibility: Participants need to be adults aged 18-75, have a good health status (ECOG PS score 0-1), and should expect to live more than 3 months. For Phase Ib, participants need to have advanced cancer and have tried other treatments that didn’t work. For Phase II, participants must have a specific type of breast cancer (HR-negative, HER2-positive) that has come back or spread.

• The study will take place over several months.
• Participants might need to visit the clinic regularly for check-ups.
• There may be risks, such as side effects from the drug.

If you are a female, you must use birth control during and for 6 months after the study. Men should also use contraception. This study will help doctors know more about the safety and effectiveness of TQB2930 for treating breast cancer.