A Study on the Use of Fluzoparib Combined With Chemotherapy for Neoadjuvant Treatment of HRD-positive, HR+/HER2- Breast Cancer

This study is a single-arm, exploratory clinical trial, which plans to enroll 28 eligible subjects with HRD-positive, ER-positive, HER2-negative early breast cancer. They will receive fluzoparib combined with standard chemotherapy, aiming to observe and evaluate the efficacy and safety of fluzoparib combined with docetaxel followed by epirubicin and cyclophosphamide in the treatment of HRD-positive, HR+/HER2- early breast cancer.

Subjects will receive fluzoparib combined with docetaxel followed by epirubicin and cyclophosphamide. After fully understanding the study and signing the informed consent form, eligible subjects identified by researchers will enter the trial period. The trial drug must be administered within 72 hours after confirmation of enrollment. Each treatment cycle lasts 3 weeks, with a total of 8 cycles. In cycles 1-4, subjects receive fluzoparib combined with docetaxel; in cycles 5-8, they receive epirubicin and cyclophosphamide. Administration continues until the end of the treatment course, or until disease progression, occurrence of intolerable toxicity, or withdrawal of informed consent by the subject.

This study is conducted in 3 phases: screening phase, treatment phase, and follow-up phase.

• Screening Phase
• Collect basic information of subjects (including date of birth, gender, ethnicity, etc.);
• Researchers will inquire about and record in detail the subject's medical history (including past medical history and current medical history) as well as drug allergy status. The doctor may require the subject to provide relevant records of diagnosis and treatment in other hospitals, so please cooperate to provide them;
• Check the subject's blood pressure, pulse, body temperature, and respiratory rate;
• Tumor diagnosis: date of pathological confirmation, pathological type, pathological stage (TNM), clinical stage.
• Tumor treatment history
• History of tumor surgery: name of surgery, date of surgery;
• History of radiotherapy: radiotherapy site, dose, start and end dates;
• History of concomitant diseases, past medication history, drug allergy history, etc.;
• Comprehensive physical examination: general condition, head and face, skin, lymph nodes, eyes, ears, nose and throat, oral cavity, respiratory system, cardiovascular system, abdomen, reproductive-urinary system, musculoskeletal system, nervous system, and mental state, etc.
• Vital signs: pulse, respiratory rate, body temperature, and blood pressure.
• ECOG score.
• Blood routine: red blood cell count (RBC), hemoglobin (Hb), platelet count (PLT), white blood cell count (WBC), neutrophil count (ANC), lymphocyte count.
• Blood biochemistry: including Glucose, TP, ALT, AST, ALP, γ-GT, ALB, TBIL, TG, CHOL, BUN, etc.
• Urine routine: white blood cells, red blood cells, urine protein.
• Coagulation function
• Virological tests: HBsAg, HBsAb, HBeAg, HBeAb, HBcAb (qualitative; if HbsAg is positive, HBV DNA quantitative detection must be performed), HCV-Ab (if positive, HCV-RNA quantitative detection must be performed), and HIV-Ab.
• 12-lead electrocardiogram: at least heart rate, QT, QTc, and P-R intervals must be indicated.
• Echocardiogram: at least left ventricular ejection fraction (LVEF) must be indicated. It should be performed within 28 days before the first administration.
• Imaging examinations: imaging examinations of the head, neck, chest, abdomen, pelvis, and bone tissue (such as enhanced MRI of the head, enhanced CT scans of the chest, upper abdomen, and pelvis, whole-body bone scan, etc.).
• Tumor tissue samples: pathological tissue samples and peripheral blood samples need to be provided before enrollment for HRD and BRCA mutation detection.
• Clinical breast examination (CBE) (including breast/axilla/supraclavicular fossa), breast ultrasound and/or mammography, and magnetic resonance imaging (MRI) scan;
• Before neoadjuvant therapy, physical marking of tumor lesions must be performed in accordance with the standard clinical operation specifications of the research center (such as skin tattooing or surgical metal clips, etc.).
• If the subject's clinical and/or ultrasound examination suggests axillary lymph node metastasis, axillary staging should include fine needle aspiration (FNA) or core needle biopsy before neoadjuvant therapy.
• Treatment Phase

After participating in the trial, subjects will receive fluzoparib combined with docetaxel followed by epirubicin and cyclophosphamide as determined by researchers until disease progression. The contents and steps to be evaluated during the trial include:

ECOG score, vital signs, blood routine, urine routine; blood biochemistry; 12-lead electrocardiogram, echocardiogram, tumor imaging examinations, adverse events, recording of concomitant medications and concomitant treatments; breast surgery, surgical diagnosis and treatment of axillary lymph nodes; postoperative case evaluation; diagnosis of recurrence or reoccurrence.

During each visit, the doctor will inform you of the time and place of the next visit. Throughout the study treatment process, subjects need to fill in the "Medication Diary Card" every day to record their medication status, as well as any uncomfortable symptoms and concomitant medications during this period.

·Follow-up Phase

When subjects complete the study treatment or terminate the study treatment early due to intolerable toxicity or other reasons, they need to go to the hospital to complete an exit study follow-up. The researcher will arrange the following examination items:

Physical examination: blood routine, urine routine, blood biochemistry, and coagulation function will be completed; Electrocardiogram examination: 12-lead electrocardiogram; Recording of adverse events; Recording of concomitant medications/concomitant treatments.