STUDY02001740;22SCH740: Estradiol For ER+ Advanced Breast Cancer (ESTHER)

• Status: Not yet recruiting
• Trial end date: 2027-05-01
• Target enrollment: 0
• Participant gender: Female

Summary

Determine whether subjects harboring ESR1-mutant/amplified breast cancer have a higher rate of clinical benefit from 17b-estradiol therapy than subjects with ESR1-wild-type breast cancer

• Phase: Phase 2
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Dartmouth-Hitchcock Medical Center
• Treatments: Estradiol

Criteria

Inclusion Criteria:

• Post-menopausal women with ER+ breast cancer.

• Metastatic or locoregional recurrence not amenable to treatment with curative

• intent.

• Received ≥1 prior line of endocrine-based therapy (e.g., including tamoxifen, aromatase inhibitors, fulvestrant, or combinations) in the advanced/metastatic setting

Exclusion Criteria:

• During the study Treatment Phase with 17b-estradiol, no concurrent anti-cancer therapies are allowed with the following exceptions:

• Exception: Trastuzumab is allowed for the treatment of subjects with a history of HER2+ disease, and will be used at the physician's discretion.

• Exception: Anti-resorptive bone therapies (e.g., bisphosphonates, denosumab) are permitted.

• Any investigational cancer therapy in the last 3 weeks.

• Known CNS disease, unless clinically stable for ≥ 3 months.

• History of any of the following:

• Deep venous thrombosis.

• Pulmonary embolism.

• Stroke.

• Acute myocardial infarction.

• Congestive heart failure.

• Previous malignancy not treated with curative intent, or with an estimated recurrence risk ≥30%.