FES Imaging to Optimize Tamoxifen for Metastatic Breast Cancer
Trial statusRecruiting
Trial phaseEarly Phase 1
Trial typeInterventional
Biological sexAll
Age19+
SponsorUniversity of Wisconsin, Madison
About this trial
Despite broad advancements in endocrine therapy for ERα+ breast cancer, resistance ultimately develops. A common driver of resistance are known ESR1 mutations that lead to constitutively active receptor signaling and transcriptional regulation that is always "turned on" despite the absence of estrogen. Patients with ESR1 mutations are expected to have decreased binding affinity for tamoxifen and thus may be underdosed on standard therapy. \[18F\]-fluoroestradiol Positron Emission Tomography/Computed tomography (FES-PET/CT) imaging is a novel functional imaging technique that can non-invasively measure ERα expression and inhibition in metastatic ERα+ breast cancer. The proposed a pilot study uses FES-PET/CT imaging to measure ERα blockade to determine the optimal dose of tamoxifen in patients with ESR1 mutations.
Eligibility criteria
Qualifiers
Estrogen receptor expression by immunohistochemistry greater than or equal to 10%
ESR1 mutation identified using a Clinical Laboratory Improvement Amendments (CLIA) certified assay via tumor biopsy tissue or circulating free DNA (cfDNA)
human epidermal growth factor receptor 2 (HER2) negative
Participants must have measurable disease as defined by RECIST 1.1 or evaluable bone disease with at least one lesion measuring 10 mm or greater in size. (Participants with bone and non-bone disease are eligible. One disease site must meet either the measurable or evaluable criteria outlined.) Participants with liver-only disease are not eligible due to the inherent hepatic uptake related to the radiopharmaceutical's hepatobiliary route of elimination.
Disqualifiers
Prior chemotherapy, radiotherapy, targeted, immunotherapy or investigational therapy within 2 weeks or major surgery within 4 weeks of study enrollment or those who have not recovered (to grade ≤ 1 or baseline) from clinically significant adverse events due to agents administered more than 2 weeks earlier (alopecia and fatigue excluded).
Participants must not be receiving an ER blocking endocrine therapy (includes fulvestrant, tamoxifen, toremifene, raloxifene) and must be off the agents for a minimum of 60 days prior to planned FES PET/CT to allow for adequate uptake of FES.
History of allergic reactions attributed to compounds of chemical or biologic composition similar to those of tamoxifen or [18F]-fluoroestradiol.
Peripheral neuropathy of severity greater than grade 1.
Trial design
Treatments tested in this trial
- Tamoxifen
- FES PET/CT
Treatment groups
12 Participants
are divided into 1 treatment groupSponsors and collaborators
Source ClinicalTrials.gov