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Recruiting Phase 2 Interventional

Acolbifene Versus Low Dose Tamoxifen for the Prevention of Breast Cancer in Premenopausal Women at High Risk for Development of Breast Cancer

ClinicalTrials.gov ID: NCT05941520

Public ClinicalTrials.gov record NCT05941520. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 6, 2026, 7:30 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

Phase IIA Trial of Acolbifene (20 mg) vs Low Dose Tamoxifen (5 mg) in Pre-menopausal Women at High Risk for Development of Breast Cancer

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

This phase IIA trial compares the effect of acolbifene versus low dose tamoxifen in preventing breast cancer in premenopausal women at high risk for developing breast cancer. The usual approach for patients at increased risk for breast cancer is to undergo yearly breast magnetic resonance imaging or ultrasound in addition to yearly mammogram. Premenopausal women at very high lifetime risk for breast cancer (greater than 50%) can consider preventive removal (mastectomy) of both breasts. Premenopausal women age 35 or older with a prior diagnosis of atypical hyperplasia, lobular carcinoma in situ, or an estimated 10-year risk of greater than or equal to 3% or estimated 10-year risk of greater than or equal to 2-5 times that of the average woman (depending on age) may be advised to consider five years of standard dose tamoxifen. Standard dose tamoxifen is four times the dose used in this study. Estrogen can cause the development and growth of breast cancer cells. Acolbifene and tamoxifen blocks the use of estrogen by breast cells. This study may help researchers measure the effects of acolbifene and low dose tamoxifen on markers of breast cancer risk in mammogram imaging, breast tissue, and in blood samples.

Study identification

NCT ID
NCT05941520
Recruitment status
Recruiting
Study type
Interventional
Phase
Phase 2
Enrollment
80 participants

Conditions and interventions

Eligibility (public fields only)

Age range
35 Years and older
Sex
Female
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Oct 9, 2024
Primary completion
Aug 22, 2027
Completion
Aug 31, 2028
Last update posted
Jul 6, 2026

2024 – 2028

United States locations

U.S. sites
4
U.S. states
4
U.S. cities
4
Facility City State ZIP Site status
City of Hope Comprehensive Cancer Center Duarte California 91010 Recruiting
Northwestern University Chicago Illinois 60611 Recruiting
University of Kansas Cancer Center Kansas City Kansas 66160 Recruiting
Ohio State University Comprehensive Cancer Center Columbus Ohio 43210 Recruiting

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT05941520, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Jul 6, 2026 · Synced Sep 6, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT05941520 live on ClinicalTrials.gov.

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