This phase 3 clinical trial compares the efficacy and safety of palazestrant with ribociclib to letrozole and ribociclib in women and men who have not received prior systemic anti-cancer treatment for advanced breast cancer.
Conditions: Breast Cancer, Locally Advanced Breast Cancer, Metastatic Breast Cancer, ER Positive Breast Cancer, HER2 Negative Breast Carcinoma
Eligibility Criteria
Inclusion Criteria
- Adult female or male participants.
- ER+, HER2- locally advanced or metastatic breast cancer that is not amenable to curative therapy.
- Evaluable disease (measurable disease per RECIST 1.1 or bone-only disease).
- De novo advanced breast cancer or with disease recurrence occurring after 12 months of completing adjuvant endocrine therapy (with or without CDK4/6 inhibitors)
- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
- Adequate hematologic, hepatic, and renal functions.
- Female participants can be pre-, peri- or postmenopausal.
- Male and pre- or peri-menopausal female participants must be willing to take a GnRH (or LHRH) agonist.
Exclusion Criteria
- Disease recurrence during adjuvant endocrine therapy
- Currently receiving or previously received systemic anti-cancer therapy for ER+, HER2- advanced breast cancer.
- Previously received treatment with fulvestrant, elacestrant or an investigational endocrine therapy in any setting.
- History of allergic reactions to study treatment.
- Any contraindications to letrozole and ribociclib.
- Symptomatic central nervous system metastases, carcinomatous meningitis, leptomeningeal disease, or a spinal cord compression that require immediate treatment.
Eligibility criteria are kept as the original English records from ClinicalTrials.gov; actual eligibility is determined by the research team's formal assessment and the informed consent form. Source: ClinicalTrials.gov, updated automatically every two weeks. Last synced: 2026年10月8日.