NCT06179303 · University of Washington
Functional Imaging in Prediction of Response to Abemaciclib for Advanced Hormone Receptor-Positive, HER2-Negative Breast Cancer
What this study is about
This phase II trial tests the accuracy of functional imaging (FFNP)-positron emission tomography (PET)/computed tomography (CT) to predict response to abemaciclib plus endocrine therapy. Abemaciclib is a drug used to treat certain types of hormone receptor positive (HR+), HER2 negative breast cancer. Abemaciclib blocks certain proteins, which may help keep tumor cells from growing.
View original scientific description
This phase II trial tests the accuracy of functional imaging (FFNP)-positron emission tomography (PET)/computed tomography (CT) to predict response to abemaciclib plus endocrine therapy. Abemaciclib is a drug used to treat certain types of hormone receptor positive (HR+), HER2 negative breast cancer. Abemaciclib blocks certain proteins, which may help keep tumor cells from growing. Endocrine therapy adds, blocks, or removes hormones that can cause cancer to grow.
Interventions
DRUG
Abemaciclib
Given PO
DRUG
Anastrozole
Given PO
PROCEDURE
Biospecimen Collection
Undergo blood sample collection
PROCEDURE
Computed Tomography
Undergo PET/CT
PROCEDURE
Diagnostic Imaging Testing
Undergo clinical imaging for tumor assessment
DRUG
Exemestane
Given PO
OTHER
Fludeoxyglucose F-18
Given IV
DRUG
Fluorine F 18 Fluoro Furanyl Norprogesterone
Given IV
DRUG
Fulvestrant
Given IM injection
BIOLOGICAL
Gonadotropin-releasing Hormone Analog
Given GnRH analog
DRUG
Letrozole
Given PO
PROCEDURE
Positron Emission Tomography
Undergo PET/CT
DRUG
Tamoxifen
Given PO
DRUG
Therapeutic Estradiol
Given PO
Primary outcome measures
Response to abemaciclib + endocrine therapy
Time frame: Up to 2 years
Non-responding: progression within 24 weeks by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 or death due to disease within 24 weeks or stable disease but lasting less than 24 weeks. Responding: defined as complete response (CR), partial response (PR) or stable disease lasting \>= 24 weeks. Quantitative deltaFFNP will be summarized by descriptive statistics (mean, median, standard deviation \[SD\], etc.) and tested against 0 by Wilcoxon signed rank test or paired t-test as appropriate, overall and by response. The dichotomized deltaFFNP will be summarized by count and percentages, overall and by response.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Men or women with metastatic or locally advanced unresectable breast cancer
- Histologically confirmed ER+ / HER2-negative, breast cancer who is a candidate for endocrine therapy with pathology from the primary tumor or metastatic/recurrent site. Based on American Society of Clinical Oncology/College of American Pathologists (ASCO CAP) Guidelines: ER+: \>= 1% of tumor cell nuclei to be immunoreactive. HER2-negative: HER2 of 0, 1+ by immunohistochemistry (IHC) or negative by fluorescence in situ hybridization (FISH).
- In the case of bone biopsy which could yield false negative ER or PR status in patients with historically HR+ disease, a patient may be eligible if the treating physician and the study chair both agree that the patient is a candidate for further endocrine therapy (ET) based treatment.
- Note that baseline PR status by IHC does not influence results of deltaFFNP-PET imaging.
- If premenopausal, the patient has to be treated with GnRH agonist for
Where
- St Louis, Missouri
- Seattle, Washington
Collaborators
Breast Cancer Research Foundation
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 16, 2026 · Source of record for eligibility and locations