Skip to main content

Adaptive Therapy With Capecitabine for Treatment of Metastatic ER Positive, HER2 Negative Breast Cancer

  • PhasePhase 2
  • StatusRecruiting
  • Planned enrollment35 people
  • Recruiting US sites1
  • SponsorMayo Clinic
  • RegistryNCT06525766

Recruitment re-checked on ClinicalTrials.gov Oct 30, 2026. Public record; not medical advice.

Adaptive Therapy With Capecitabine for Treatment of Metastatic ER Positive, HER2 Negative Breast Cancer: a one-minute explainerNCT065257661 min

Eligibility

Who can join

The film gives the main points. The full list below is copied from the registry; the study team makes the final decision.

  • Age18 Years to no maximum
  • SexAll
  • Healthy volunteersNo

You may be able to join if

  • PRE-REGISTRATION: Provide written informed consent Note: Pre-registration should occur prior to screening research blood draws being completed
  • PRE-REGISTRATION: Provider anticipates the patient will begin on capecitabine within 14 days or has started capecitabine within the past 42 days and has had a maximum of two cycles Note: Pre-registration should occur prior to screening research blood draws being completed
  • REGISTRATION - INCLUSION CRITERIA
  • Age ≥ 18 years
  • Histological confirmation of estrogen-receptor positive (ER+), HER2-negative overexpression or amplification negative as per American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines, metastatic breast cancer
  • Measurable disease. Bone only disease allowed if associated with soft tissue component that is measurable by Response Evaluation Criteria is Solid Tumors (RECIST) 1.1 criteria
  • Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0, 1 or 2
  • Hemoglobin ≥ 9.0 g/dL (obtained ≤ 14 days prior to registration), no transfusions allowed ≤ 14 days prior to registration
  • Absolute neutrophil count (ANC) ≥ 1500/mm^3 (obtained ≤ 14 days prior to registration)
  • Platelet count ≥ 100,000/mm^3 (obtained ≤ 14 days prior to registration)
  • Total bilirubin ≤ 1.5 x upper limit of normal (ULN) (obtained ≤ 14 days prior to registration)
  • Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3 x ULN (≤ 5 x ULN for patients with liver involvement) (obtained ≤ 14 days prior to registration)
  • Calculated creatinine clearance ≥ 30 ml/min using the Cockcroft-Gault formula (obtained ≤ 14 days prior to registration)
  • Negative serum or urine pregnancy test done ≤ 7 days prior to registration, for persons of childbearing potential only. NOTE: If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required
  • Provide written informed consent
  • Ability to complete questionnaire(s) by themselves or with assistance
  • Willingness to provide mandatory blood specimens for correlative research
  • Ability to undergo re-staging CT scans as required by the protocol
  • Note: for patients who have had up to two cycles of capecitabine prior to joining the study, they must have had their initial CT imaging completed within 28 days of their first dose of capecitabine
  • Willing to return to enrolling institution at the specified frequency for follow-up (during the active monitoring phase of the study)
  • Cohort 2 only: Stable disease, partial or complete response on imaging after beginning capecitabine

You cannot join if

  • Prior chemotherapy or use of antibody drug conjugate in the metastatic setting
  • Note - Cohort 2 only: Patients can have had up to two cycles of capecitabine before joining the study
  • Any of the following, because this study involves an agent that has known genotoxic, mutagenic and teratogenic effects:
  • Pregnant persons
  • Nursing persons
  • Persons of childbearing potential who are unwilling to employ adequate contraception
  • Any of the following prior therapies:
  • Major surgery ≤ 3 weeks prior to registration
  • Radiation therapy ≤ 2 weeks prior to registration
  • Evidence of visceral crisis or impending cord compression
  • Evidence of uncontrolled brain metastasis requiring whole brain irradiation or intervention
  • Uncontrolled intercurrent illness including, but not limited to:
  • ongoing or active infection
  • symptomatic congestive heart failure
  • unstable angina pectoris
  • uncontrolled cardiac arrhythmia
  • chronic oxygen dependence
  • respiratory failure
  • or psychiatric illness/social situations that would limit compliance with study requirements
  • Receiving any other investigational agent which would be considered as a treatment for the primary neoplasm
  • Other active malignancy ≤ 3 years prior to registration. EXCEPTIONS: Non-melanotic skin cancer or carcinoma-in-situ of the cervix
  • If there is a history of prior malignancy, they must not be receiving other cancer specific treatment. Except for antiestrogen treatment (aromatase inhibitors or selective estrogen modulators) for their cancer are permitted if they meet other eligibility criteria. Denosumab and zoledronic acid, are permitted as established adjunct therapies per guidelines
  • History of myocardial infarction ≤ 6 months prior to registration, or congestive heart failure requiring use of ongoing maintenance therapy for life-threatening ventricular arrhythmias
  • Patients known to have certain homozygous or compound heterozygous dihydropyrimidine dehydrogenase (DPYD) variants that result in complete absence of deoxypyridinoline (DPD) activity. Test results do not need to be available prior to registration
  • History of severe hypersensitivity reactions to fluorouracil or capecitabine

The treatment

How it is intended to work

This is how the treatment is meant to work. Whether it helps, and how safe it is, is what this trial is testing.

Treatments listed in the registry

  • Biospecimen Collection (Procedure): Undergo blood sample collection
  • Bone Scan (Procedure): Undergo bone scan
  • Capecitabine (Drug): Given PO
  • Computed Tomography (Procedure): Undergo CT
  • Magnetic Resonance Imaging (Procedure): Undergo MRI
  • Questionnaire Administration (Other): Ancillary studies

The study

Treatment groups

Na · Single Group · masking: None

Treatment (capecitabine) (Experimental)

See Detailed Description.

What it involves

Procedures

As the registry describes them. Requirements to join, such as a tissue sample, are in the eligibility list above even when on-study procedures are optional. Ask the study team which steps apply to you.

  • blood samples: Part of the study plan; some time points described as optional
  • CT scans: Part of the study plan; some time points described as optional
  • MRI: Part of the study plan; some time points described as optional
  • questionnaires: Part of the study plan
  • bone scan: Part of the study plan; some time points described as optional

Goals

What the study measures

Main goals

  • Ability to achieve adaptive therapy (AT) (Up to 5 years)

Other goals

  • Time to progression
  • Overall survival (OS)
  • Cumulative dose
  • Incidence of adverse events (AEs)
  • Quality of life - EORTC-QLQ-C30

Planned enrollment: 35 (estimated).

Where

Recruiting US sites

  • Mayo Clinic in Arizona, Scottsdale, Arizona

Site status as of Oct 30, 2026. Check the live record before contacting a site.

Sources

Where this comes from

Registry record reviewed as fetched Oct 30, 2026, last updated by the sponsor Aug 11, 2026. Public record; not medical advice.

For you, or someone you love

Whether or not this trial is the one, bring AI into your corner.

A complex diagnosis brings new questions every week, in a trial and out of one. Triangle keeps your whole medical file together, reads it with you in plain language, and helps you and your family decide what to ask next.

Start your 7-day free trial

Then $9 a month. Cancel anytime.

  • Every record in one place

    Requested from your hospitals and clinics through the national networks. Add scans, pathology and anything on paper.

  • Read in plain words

    Reports explained as they come in, with lab values you can follow before treatment, during a trial and after.

  • Ready for every appointment

    Ask about your own file, and walk in with questions for your oncologist or the trial team.

  • Your people, in the loop

    Share one profile with the family helping you, and with your doctors.

Members also get a deeper analysis of their records and any sequencing data, including clinical trials that may fit, reviewed by a licensed physician before they receive it.

Already in a trial?

It turns into a project to manage: visits, scans, labs, side effects and paperwork. Triangle keeps it organized in one place for you or for whoever's helping.

Organize my trial

7-day free trial, then $9 a month. Cancel anytime.