Actively Recruiting
Phase IIA Trial of Acolbifene (20 mg) vs Low Dose Tamoxifen (5 mg) in Premenopausal Women at High Risk for Breast Cancer
Led by National Cancer Institute (NCI) · Updated on 2026-05-13
80
Participants Needed
4
Research Sites
53 weeks
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating acolbifene versus low dose tamoxifen for preventing breast cancer in premenopausal women at high risk. This phase IIA trial focuses on women aged 35 or older with increased lifetime breast cancer risk due to prior diagnoses like atypical hyperplasia or lobular carcinoma in situ, or calculated risk scores. The study aims to measure changes in breast tissue gene expression, mammographic density, and quality of life related to menopause symptoms. Participants are randomized to receive either acolbifene 20 mg or tamoxifen 5 mg orally once daily for 6 months, provided there is no disease progression or unacceptable side effects. Both groups undergo 3D mammography, blood sample collections, and random periareolar fine needle aspiration (RPFNA) during screening and treatment. After completing the treatment period, follow-up occurs between 21 and 35 days. Throughout the study, participants will have assessments including breast imaging to measure fibroglandular volume changes, blood tests for hormone levels, and questionnaires on menopause-specific quality of life and hot flashes. Researchers will monitor gene expression changes in breast tissue and track safety and treatment adherence. The primary outcome is the change in AGR2 gene expression over six months, with secondary outcomes assessing estrogen response, mammographic density, and symptom scores.
CONDITIONS
Brief Title
Acolbifene Versus Low Dose Tamoxifen for the Prevention of Breast Cancer in Premenopausal Women at High Risk for Development of Breast Cancer
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Age 35 years or older
- Clinically premenopausal with regular menstrual cycles or suppressed periods due to contraceptive device or hysterectomy with intact ovaries
- Not planning pregnancy for at least 12 months
- Women of child-bearing potential must use effective birth control 8 weeks before and after study completion
- Increased breast cancer risk documented by prior biopsy showing DCIS, LCIS, atypical hyperplasia, or gene mutations associated with risk
- Increased risk by model calculations including 10-year risk >= 3% or lifetime risk >= 25%
- At least one unaffected untreated breast for fine needle aspiration
- ECOG performance status <= 2 or Karnofsky score >= 60%
- Normal liver and kidney function within 180 days prior to randomization
- Willingness and ability to comply with study visits, treatment, and procedures
- Ability to understand and sign informed consent
You will not qualify if you...
- Bilateral breast implants
- Pregnancy or current breastfeeding or nursing within past 12 months
- Prior invasive breast cancer within past 5 years
- Other invasive cancer > T1 stage within past 5 years except non-melanoma skin cancer
- BRCA1/2 or PALB2 gene mutations
- Diabetes requiring prescription medication
- Prior deep vein thrombosis, pulmonary embolus, or stroke
- Chronic liver disease including NASH and hepatitis B or C
- HIV infection
- Current use of prescription anticoagulants
- Unable or unwilling to stop aspirin use at least 3 weeks before fine needle aspiration
- Recent changes in oral contraceptives or hormonal progestin devices within 8 weeks
- Current or recent use of progesterone/progestin injections or implants
- Use of other investigational agents
- Prior treatment with acolbifene or tamoxifen for more than 2 months
- Current use of prescription immunosuppressive drugs
- Allergic reactions to tamoxifen, acolbifene, or similar compounds
- Uncontrolled illness or psychiatric/social conditions limiting study compliance
AI-Screening
AI-Powered Screening
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Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - 6 months
Participants receive either acolbifene 20 mg or low dose tamoxifen 5 mg orally once daily for 6 months while undergoing periodic assessments including 3D mammography, blood sample collection, and random periareolar fine-needle aspiration (RPFNA).
1 baseline visit and 1 visit at end of treatment; additional visits for RPFNA during day 1-10 of menstrual cycle or as scheduled
Duration - 3 to 5 weeks
Participants are followed up between 21 to 35 days after completing study treatment to monitor safety and outcomes.
1 follow-up visit (in-person)
Trial Site Locations
Total: 4 locations
1
City of Hope Comprehensive Cancer Center
Duarte, California, United States, 91010
Actively Recruiting
2
Northwestern University
Chicago, Illinois, United States, 60611
Actively Recruiting
3
University of Kansas Cancer Center
Kansas City, Kansas, United States, 66160
Actively Recruiting
4
Ohio State University Comprehensive Cancer Center
Columbus, Ohio, United States, 43210
Actively Recruiting
How is the study designed?
Study Type
INTERVENTIONAL
Masking
DOUBLE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
PREVENTION
Number of Arms
2
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