A Study of TQB3616 Capsules Combined With Fulvestrant Injection in Subjects With Advanced Breast Cancer

Inclusion Criteria: * 1.Understood and signed an informed consent form. 2.Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1; Life expectancy ≥ 3 months. 3. Histopathologically confirmed HR positive and HER2 negative advanced or metastatic breast cancer. 4.Cohort 1: patients had received ≤1 line of treatment. 5.Cohort 2: patients had not previously received systemic antitumor therapy. 6.Has at least one measurable lesion according to RECIST1.1 criteria. 7.Adequate laboratory indicators. Exclusion Criteria: * 1\. Concomitant disease and medical history: 1. Has other malignant tumors within 3 years; 2. Has multiple factors affecting oral medication; 3. Unalleviated toxicity ≥ grade 1 due to any previous anticancer therapy; 4. Has active or uncontrolled severe infections before the first dose; 5. Cirrhosis, active hepatitis# 6. Have a history of immunodeficiency; 2. Tumor-related symptoms and treatment: <!-- --> 1. Has central nervous system metastases (CNS) and/or cancerous meningitis or leptomeningeal carcinomatosis; 2. Had received chemotherapy within 3 weeks prior to the first dose, and had received radiotherapy , hormone therapy, or other anti-tumor therapy within 2 weeks prior to the first dose; 3. Has uncontrollable pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures. 3\. Has known to be allergic to Fulvestrant injection , TQB3616 or any excipient. 4\. Has Participated in other clinical trials within 4 weeks before first dose. 5. According to the judgement of the investigators, there are other factors that may lead to the termination of the study.