NCT06502691

[18F]FTT Positron Emission Tomography for the Measurement of PARP Tumor Expression in Patients With Metastatic Breast Cancer

[18F]FTT Positron Emission Tomography (PET) in Patients With Metastatic Breast Cancer

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 22 (estimated)
• Sponsor: University of Washington · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This clinical trial studies how well fluorine F 18 fluorthanatrace (\[18F\]FTT) positron emission tomography (PET) works in imaging patients with breast cancer that has spread from where it first started (primary site) to other places in the body (metastatic) who are receiving standard of care (SOC) poly (ADP-ribose) polymerase (PARP) inhibitors with or without immune checkpoint inhibitors (ICI) to be able to detect clinical response to PARP inhibitor ± ICI treatment. \[18F\]FTT is a radiotracer that targets and binds to PARP1 which can potentially be used for the imaging of PARP1 expression using PET. Once administered, \[18F\]FTT targets and binds to PARP1. Upon PET, PARP1-expressing tumor cells can be visualized. PET is an established imaging technique that utilizes small amounts of radioactivity attached to very minimal amounts of tracer, in the case, \[18F\]FTT. Because some cancers take up \[18F\]FTT it can be seen with PET. PARP inhibitors work as a targeted therapy by blocking an enzyme involved in repairing cell damage. It may cause tumor cells to die. ICI may help the body's immune system attack the cancer and may interfere with the ability of tumor cells to grow and spread. Combining \[18F\]FTT with a PET scan may help detect tumor cells better in patients with metastatic breast cancer who are receiving standard of care PARP inhibitors with our without ICI treatment.

Detailed description

OUTLINE: Patients are assigned to 1 of 2 arms. Arm I: Patients receive \[18F\]FTT intravenously (IV) and undergo PET scan 60-75 minutes later on day 1 of initiating SOC PARP inhibitor ± ICI therapy and again at 12 weeks. At least 1-7 days later, patients undergo SOC FDG PET/computed tomography (CT) and follow up scans at 12 weeks and 6 months. Patients may also undergo tissue biopsy during screening and during follow up. Arm II: Patients receive \[18F\]FTT IV and undergo PET scan 60-75 minutes later on day 1 of initiating SOC PARP inhibitor ± ICI therapy. At least 1-7 days later, patients undergo SOC FDG PET/CT and follow up scans at 12 weeks and 6 months. Patients may also undergo tissue biopsy during screening. After initial \[18F\]FTT PET imaging, patients are followed-up to 6 months or until disease progression.

Conditions

• Anatomic Stage IV Breast Cancer AJCC v8
• Metastatic Breast Carcinoma

Interventions

Type	Name	Description
OTHER	Best Practice	Receive of standard care
PROCEDURE	Biopsy of Breast	Undergo breast biopsy
PROCEDURE	Computed Tomography	Undergo FDG PET/CT
OTHER	Electronic Health Record Review	Ancillary studies
OTHER	Fludeoxyglucose F-18	Given FDG
RADIATION	Fluorine F 18 Fluorthanatrace	Given IV
DRUG	Immune Checkpoint Inhibitor	Receive ICI treatment
DRUG	Poly (ADP-Ribose) Polymerase Inhibitor	Receive PARP inhibitor treatment
PROCEDURE	Positron Emission Tomography	Undergo \[18F\]FTT PET
PROCEDURE	Positron Emission Tomography	Undergo FDG PET/CT

Timeline

• Start date: 2026-02-26
• Primary completion: 2027-12-31
• Completion: 2030-12-31
• First posted: 2024-07-16
• Last updated: 2026-03-02

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study