Fluoroestradiol F-18 for Metastatic hormone receptor-positive HER2-negative breast cancer

Inclusion criteria

• {"criterion_text":"- At least 18 years old"}
• {"criterion_text":"- Histologically - or cytologically-proven diagnosis of HR+ (Estrogen Receptor: ≥10%)/HER2- carcinoma of the breast with evidence of either locally advanced disease not amenable to resection or radiation therapy with curative intent or metastatic disease not amenable to curative therapy"}
• {"criterion_text":"- Appropriate candidates for endocrine therapy (no visceral crisis, highly symptomatic disease or rapidly progressing disease)"}
• {"criterion_text":"- Measurable disease per RECIST or bone only disease with evaluable lesions"}
• {"criterion_text":"- ≥50% of measurable lesions defined as avid (SUVmax≥1.5) at 18F-FES-PET/CT"}
• {"criterion_text":"- Progressed on prior treatment with a CDK4/6 inhibitor in combination with anastrozole or letrozole (+ LHRH agonist for male or premenopausal female patients), in first line setting for metastatic disease, for at least 12 months and there must have been evidence of disease control (at least stable disease per RECIST v.1.1)"}
• {"criterion_text":"- ECOG performance status 0 or 1"}
• {"criterion_text":"- Adequate organ function"}

Exclusion criteria

• {"criterion_text":"- Prior treatment with fulvestrant, elacestrant or investigational SERD or ER antagonist in metastatic or early disease"}
• {"criterion_text":"- Prior treatment with tamoxifen or SERD alone or combined with CDK4/6i in the metastatic setting"}
• {"criterion_text":"- Bisphosphonates or RANKL inhibitors initiated or dose changed < 3 months prior to first dose of study drug"}
• {"criterion_text":"- Radiation therapy within 14 days (28 days for brain lesions) before the first dose of study drug"}
• {"criterion_text":"- Presence of symptomatic metastatic visceral disease or meningeal disease"}
• {"criterion_text":"- Pregnancy at the time of the study entry"}
• {"criterion_text":"- Diagnosis of inflammatory breast cancer and chest wall disease"}

Primary endpoints

• {"endpoint_text":"- 6-month PFS rate per RECIST v 1.1","definition_or_measurement_approach":"Progression-free survival rate at 6 months measured according to RECIST v1.1"}

Secondary endpoints

• {"endpoint_text":"- Adverse Events per CTCAE 5.0","definition_or_measurement_approach":"Safety assessed by recording adverse events and grading per CTCAE v5.0"}
• {"endpoint_text":"- Median Overall Survival","definition_or_measurement_approach":"Overall survival measured as time from enrolment to death; median OS to be reported"}
• {"endpoint_text":"- Overall Response Rate per RECIST 1.1","definition_or_measurement_approach":"Objective response assessed per RECIST v1.1; overall response rate calculated accordingly"}
• {"endpoint_text":"- Median QoL change from baseline to week 8 of treatment measured by EORTC QLQ-C30 and FACT-ES v.4 questionaries","definition_or_measurement_approach":"Quality of life change from baseline to week 8 measured using EORTC QLQ-C30 and FACT-ES v4 questionnaires; median change reported"}
• {"endpoint_text":"- 6-months Progression-free survival (PFS) rate per RECIST 1.1 according to baseline FES-SUV and SUV variation of FES","definition_or_measurement_approach":"6-month PFS per RECIST v1.1 stratified/analysed according to baseline 18F-FES SUV and changes in FES SUV"}

Italy

Earliest CTIS Part Ii Submission Date

15-09-2025

Latest Decision Or Authorization Date

10-10-2025

Processing Time Days

25

Number Of Sites

1

Number Of Participants

26

Primary sponsor

Full Name

Istituto Europeo Di Oncologia S.r.l.

Organisation Type

Hospital/Clinic/Other health care facility

Country Of Registered Address

Italy

Third parties

• {"country":"Italy","full_name":"Consorzio Per Valutazioni Biologiche E Farmacologiche","duties_or_roles":"Sponsor duties (code 8)","organisation_type":"Pharmaceutical company"}
• {"country":"","full_name":"GE Healthcare Limited","duties_or_roles":"Monetary support (listed in sourceOfMonetarySupport)","organisation_type":""}
• {"country":"","full_name":"GUARDANT HEALTH, INC.","duties_or_roles":"Monetary support (listed in sourceOfMonetarySupport)","organisation_type":""}
• {"country":"","full_name":"Menarini Berlin Chemie","duties_or_roles":"Monetary support (listed in sourceOfMonetarySupport)","organisation_type":""}