Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer
Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer
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.
Breast
Phase III
Adults
Hormonal Therapy,
Mol. targeted/Immunotherapy/Biologics
Letrozole (Femara),
Palazestrant,
Ribociclib
Abramson, Vandana
National
Vanderbilt University
06-25-2026
Eligibility
18 Years and older
ALL
false
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.
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.
