A Phase III Trial Comparing HRS-8080 With Standard Endocrine Therapy in Patients With Intermediate or High Risk Early Breast Cancer

Inclusion criteria

• Female patients aged ≥ 18 and ≤ 75 years. Premenopausal patients must meet the eligibility of LHRH agonist therapy during the study period.
• Histologically confirmed invasive breast cancer by postoperative pathology, having received at least 2 years, but no more than 5 years, of adjuvant endocrine therapy.
• No evidence of recurrent or metastatic disease after surgery.
• ECOG performance status of 0 or 1.
• Adequate organ and bone marrow function.
• Women of childbearing potential must have a negative serum pregnancy test within 7 days prior to randomization and be willing to use acceptable non-hormonal contraception methods from the time of informed consent until 7 months after the last dose of the study drug.
• Any acute toxicities from previous anti-tumor therapy have resolved to Grade 0-1 (per CTCAE v5.0).
• The patient has provided written informed consent (ICF), and is willing and able to comply with scheduled visits, treatment plans, laboratory tests, and other study procedures.

Exclusion criteria

• Tumor clinical stage IV (metastatic) breast cancer.
• History and/or treatment of any malignancy other than breast cancer within 5 years prior to randomization.
• History of severe pulmonary disease, such as interstitial lung disease.
• Concurrent or potential use of any anti-tumor therapy not specified in the study protocol.
• Major surgical procedure within 4 weeks prior to randomization.
• HIV infection or known AIDS, active hepatitis B, hepatitis C, or co-infection with hepatitis B and C.
• Poor cardiac function.
• Severe infection within 4 weeks prior to randomization.
• History of drug allergy.
• History of organ transplantation.
• History of substance abuse.
• Women within 1 year postpartum or who are currently breastfeeding.
• Patients deemed by the investigator as unsuitable for participation in this study.