Phase 3 Study of Elacestrant Plus Everolimus Versus Elacestrant Alone in Adults With ER-Positive, HER2-Negative, ESR1-Mutated Advanced Breast Cancer Progressing After Endocrine Therapy and CDK46 Inhibitors

What this Trial Is About

Researchers are evaluating a treatment for advanced breast cancer that is estrogen receptor-positive, HER2-negative, and has a specific ESR1 gene mutation. The study aims to find out how well a combination of elacestrant, a selective estrogen receptor degrader, and everolimus, a kinase inhibitor, works in patients whose cancer has progressed despite prior endocrine therapy and CDK46 inhibitor treatment. The study follows strict guidelines to ensure patient safety and compliance with international clinical standards. Participants will be randomly assigned to one of two groups. One group will receive elacestrant at 345 mg plus everolimus at 7.5 mg orally once daily, while the other group will receive elacestrant at the same dose plus a placebo instead of everolimus. Treatments will be given in 28-day cycles and continue until disease progression, unacceptable side effects, or other reasons for stopping the treatment occur. After stopping treatment, patients will be followed every three months for up to one year to monitor survival and any new cancer therapies. During the study, patients will undergo scans such as CT or MRI to confirm disease status, and tests to assess tumor markers and gene mutations. Researchers will monitor treatment effects, safety, and quality of life using questionnaires like the EQ-5D-5L and EORTC QLQ-C30 and QLQ-BR42. Side effects, blood counts, liver and kidney function, heart activity, and overall health status will be regularly checked. The main outcome is progression-free survival, measuring how long patients live without cancer worsening during treatment, with other outcomes including overall survival and treatment response. The total study duration for each participant averages about 12 months.

Elacestrant + Everolimus in Patients ER+/HER2-, ESR1mut, Advanced Breast Cancer Progressing to ET and CDK4/6i.