Study of 18F-FFNP Breast PET/MRI for Breast Cancer

This study is looking at a new way to predict how well breast cancer patients will respond to hormone therapy. Researchers are using a special imaging scan called 18F-FFNP PET/MRI, which combines a PET scan (Positron Emission Tomography) and an MRI (Magnetic Resonance Imaging). You would receive a small amount of a drug called 18F-fluorofuranylnorprogesterone (18F-FFNP) and an FDA-approved gadolinium-based contrast agent for the scans. You would also take anastrozole, a hormone-based chemotherapy, daily for at least 14 days. The study aims to see if changes in the 18F-FFNP uptake on these scans can predict how well the treatment is working. This study is for postmenopausal women with newly diagnosed breast cancer that is positive for the progesterone receptor (PR+). The study is currently unclear on its recruitment status and plans to enroll 53 participants.

Study design: This is an interventional study, meaning participants will receive specific treatments and tests. It plans to enroll 53 participants.
What's involved: You would receive an infusion of 18F-FFNP and a contrast agent, undergo breast PET/MRI scans, and take anastrozole daily for at least 14 days. Blood samples will be collected at multiple times after the 18F-FFNP injection.
Compensation: Not stated in the trial record.
Follow-up: Changes in PET/MRI scans and tumor scores will be measured up to 7 weeks on study.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

Study of 18F-FFNP Breast PET/MRI

Recruiting

PHASE2Ages 18+InterventionalDiagnostic

University of Wisconsin, Madison

~53 participants

Updated 2026-08-31 on ClinicalTrials.gov

What's tested:18F-fluorofuranylnorprogesteronePositron Emissions Tomography / Magnetic Resonance ImagingAnastrozoleBlood SamplingFDA-approved gadolinium-based intravenous contrast agent

At a glance

Recruiting sites

1 of 1 listed site is recruiting right now

RecruitingSuspended, closed, or not yet open

What they're measuring

Percentage change in 18F-FFNP uptake between baseline and follow-up PET/MRI scans

Measured over up to 4 weeks on study and up to 7 weeks on study

+1 more outcome measured

Conditions

Breast Cancer

Where it's being run

1 sites across 1 states

Wisconsin1

Study leadership

Amy M Fowler, MD, PHD · PRINCIPAL_INVESTIGATOR · UW Carbone Cancer Center

Who to contact

Cancer Connect

[email protected]

800-622-8922

Email the study team

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Do you actually qualify for this trial?

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Eligibility criteria

Inclusion

Postmenopausal status defined by either

prior bilateral oophorectomy

age greater than or equal to 60 years of age

age less than 60 years of age and amenorrheic for 12 or more months in the absence of prior chemotherapy, tamoxifen, toremifene or ovarian suppression and FSH and estradiol in the postmenopausal range per local normal range (Group 2 only)

Diagnosis of biopsy-proven invasive breast cancer measuring at least 1.0 cm in diameter by any imaging modality. Malignancy may be located within the breast, axilla (e.g. metastatic axillary lymph node), or both the breast and axilla

Biopsy-proven PR-positive invasive breast cancer

Definitive surgical excision of the primary tumor planned without neoadjuvant therapy; defined as therapy (chemotherapy, targeted therapy, radiation therapy or endocrine therapy) given to decrease the size of the tumor prior to planned surgery. (Group 2 only)

Exclusion

Inability or unwillingness to provide informed consent to the study

HER2-positive breast cancer, as defined by immunohistochemical staining 3+ OR positive by in situ hybridization (Group 2 only)

PR and Ki67 IHC slides or FFPE tissue blocks from clinical breast biopsy not available

Patients who have completed neoadjuvant chemotherapy, endocrine therapy, targeted therapy, surgical resection, or radiation for the current biopsy-proven malignancy (Group 2 only)

Patients who are planning to undergo anastrozole as standard of care neoadjuvant therapy

Patients who are currently taking aromatase inhibitors or ER antagonists (tamoxifen, raloxifene)

Patients with breast expanders

Patients who are pregnant or lactating

Patients with clinical contraindication for use of aromatase inhibitors (AI) while on study as determined by investigator (Group 2 only)

Patients with a contraindication to gadolinium-based contrast agents, including allergy or impaired renal function (per UW Health Guidelines)

Patients with a history of allergic reaction attributable to compounds of similar chemical or biologic composition to 18F-FFNP

Patients with history of allergic reaction to anastrozole (Group 2 only)

Patients in liver failure as judged by the patient's physician

Patients with standard contraindications to MRI (per UW Health Guidelines)

Patients requiring conscious sedation for imaging are not eligible; patients requiring mild, oral anxiolytics for the clinical MRI scan will be allowed to participate as long as the following criteria are met:

The patient has their own prescription for the medication

The informed consent process is conducted prior to the self-administration of the medication.

The patient comes to the research visit with a driver.

Patients unable to lie prone for 45 minutes for imaging

What this trial measures

Percentage change in 18F-FFNP uptake between baseline and follow-up PET/MRI scansup to 4 weeks on study and up to 7 weeks on study
Tumor uptake values of 18F-FFNP will be obtained from the attenuation corrected PET component of the simultaneous breast 18F-FFNP PET/MRI research scan according to the procedures detailed in the imaging manual and the FDA IND.
Percentage change in tumor Ki67 proliferation score, as a surrogate measure of endocrine sensitivityup to 4 weeks on study and up to 7 weeks on study
Baseline Ki67 proliferation immunohistochemistry score will be obtained from the existing clinical standard-of-care breast biopsy. Post-treatment K67 proliferation immunohistochemistry score will be obtained from the surgical specimen after excision. Treatment response is defined as a reduction in Ki67 score of greater than or equal to 60 percent. Treatment nonresponse is defined as a reduction of less than 60 percent.

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