A Study to Evluate Efficacy and Safety of HRS-8080 Combined With Dalpiciclib in Patients With Advanced or Metastatic Breast Cancer Resistant to Adjuvant Endocrine Therapy.

Exclusion Criteria

• •1. Patients with rapidly progressing disease, as judged by the investigator to be unsuitable for endocrine therapy;
• •2. Patients who have previously received fulvestrant or other novel SERMs (excluding tamoxifen and toremifene);
• •3. Patients with uncontrolled brain metastases, carcinomatous meningitis, or spinal cord compression;
• •4. Patients with a history of clinically significant cardiovascular disease;
• •5. Participants who have not recovered from adverse effects caused by prior therapies;
• •6. Participants with a history of another malignancy within the past 5 years or currently having another malignancy;
• •7. Known hypersensitivity to HRS-8080, fulvestrant, dalpiciclib, or any of their components, etc.