NCT07434128

Mammogram Pretreatment With Ulipristal Acetate

Progesterone Receptor Modulator Mammogram Pretreatment for Premenopausal People With a History of Extremely Dense Breast Tissue

• Status: Not Yet Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 26 (estimated)
• Sponsor: OHSU Knight Cancer Institute · Academic / Other
• Sex: Female
• Age: 18 Years – 50 Years
• Healthy volunteers: Not accepted

Summary

This phase II trial tests whether taking ulipristal acetate prior to a mammogram decreases breast density for people with a history of extremely dense breast tissue. One limitation to breast cancer screening with mammography is dense breast tissue, which decreases the sensitivity of screening as breast density masks cancer and precancerous lesions. Ulipristal acetate lowers the amount of progesterone made by the body which may temporarily decrease the density of the breast tissue, allowing for a more accurate mammogram for people with extremely dense breast tissue.

Detailed description

PRIMARY OBJECTIVE: I. To evaluate change in percent dense area from antecedent to study screening mammograms. SECONDARY OBJECTIVES: I. To assess for menstrual cycle phase following this regimen of ulipristal acetate (UPA). II. To assess adherence, tolerability and acceptability of the short course of UPA prior to a mammogram. EXPLORATORY OBJECTIVES: I. To determine the presence of radiographic changes in clinical breast density on screening mammograms following a course of UPA. II. To characterize a change in background parenchymal enhancement (BPE) on breast magnetic resonance (MR). III. To describe the effect of the intervention on routine clinical care. IV. To determine the longitudinal effect of the intervention on primary objective (clinical breast density score). OUTLINE: Patients receive ulipristal acetate orally (PO) every 5 days for 4 doses in the absence of unacceptable toxicity (study days 1, 5, 10 and 15). Patients then undergo a mammogram on study day 20. Patients also undergo base magnetic resonance imaging (MRI) and blood sampling which will be repeated on study day 20. After completion of study intervention, patients are followed up at 1-7 days and may be followed up to 24 months for results of subsequent screening mammograms.

Conditions

• Mammography Screening
• Breast Density

Interventions

Type	Name	Description
PROCEDURE	Biospecimen Collection	Undergo blood sample collection
PROCEDURE	Magnetic Resonance Imaging	Undergo MRI
PROCEDURE	Mammogram	Participants will undergo their standard of care mammogram.
OTHER	Survey Administration	Ancillary studies
DRUG	Ulipristal Acetate	Given orally

Timeline

• Start date: 2026-04-02
• Primary completion: 2027-12-31
• Completion: 2027-12-31
• First posted: 2026-02-25
• Last updated: 2026-02-25

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study