Recruiting
Phase 2

Estradiol

Sponsor:

Dartmouth-Hitchcock Medical Center

Code:

NCT05716516

Conditions

Metastatic Breast Cancer

Eligibility Criteria

Sex: Female

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Estradiol

Study Details

Brief 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

Conditions

Metastatic Breast Cancer

Study ID

NCT05716516

Start date

May 4, 2023

Status verified date

Apr, 2026

Completion date

May, 2027

Anticipated

Primary completion date

May, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 18+

Healthy Volunteers: Not accepted

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%.

Study Design

Enrollment

36 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

other: Treatment Arm

Treatment Phase: Patients will be treated with 17b-estradiol until disease progression. At this point, the patient will end protocol therapy

Interventions

Estradiol

Estradiol is a therapeutic option for the treatment of advanced ER+ breast cancer

Primary outcome measure

  • Clinical Benefit Rate [ Time Frame: 12 months ]

Central Contacts and Locations

Central contacts

Research Nurse

1-800-639-6918Cancer.Research.Nurse@dartmouth.edu

Locations

Dartmouth-Hitchcock Medical Center

Recruiting

Lebanon, New Hampshire, United States, 03756

More Information

Sponsor

Dartmouth-Hitchcock Medical Center

Last update posted

May 5, 2026

Last verified

Apr, 2026

Keywords

  • Metastatic
  • Locally advanced
  • Estradiol therapy
  • Estrogen therapy

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Dartmouth-Hitchcock Medical Center on 2026-05-05.