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OncoMatch/Clinical Trials/NCT06525766

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

Is NCT06525766 recruiting? Yes, currently enrolling (May 2026). This Phase 2 trial studies Capecitabine for anatomic stage iv breast cancer ajcc v8.

Phase 2RecruitingMayo ClinicNCT06525766Data as of May 2026

Treatment: CapecitabineThis phase II trial evaluates the effect of capecitabine on tumor response using imaging and tumor markers to adjust dose (adaptive therapy) in patients with estrogen receptor (ER) positive, HER2 negative breast cancer that has spread from where it first started to other areas in the body (metastatic). Capecitabine is in a class of medications called antimetabolites. It is taken up by tumor cells and breaks down into fluorouracil, a substance that kills tumor cells. Adaptive therapy with capecitabine based on tumor burden response may slow or stop the growth of tumor cells in patients with metastatic ER positive, HER2 negative breast cancer.

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Extracted eligibility criteria

Cancer type

Breast Carcinoma

Biomarker criteria

Required: ESR1 overexpression (positive)

estrogen-receptor positive (ER+)

Required: HER2 (ERBB2) overexpression (negative)

HER2-negative overexpression or amplification negative as per ASCO/CAP guidelines

Required: HER2 (ERBB2) amplification (negative)

HER2-negative overexpression or amplification negative as per ASCO/CAP guidelines

Excluded: DPYD homozygous or compound heterozygous variants resulting in complete absence of DPD activity

Patients known to have certain homozygous or compound heterozygous dihydropyrimidine dehydrogenase (DPYD) variants that result in complete absence of deoxypyridinoline (DPD) activity

Disease stage

Required: Stage IV

Metastatic disease required

Performance status

ECOG 0–2(Ambulatory, capable of self-care)

Prior therapy

Cannot have received: chemotherapy

Exception: in the metastatic setting

Prior chemotherapy or use of antibody drug conjugate in the metastatic setting

Cannot have received: antibody-drug conjugate

Exception: in the metastatic setting

Prior chemotherapy or use of antibody drug conjugate in the metastatic setting

Cannot have received: major surgery

Exception: ≤ 3 weeks prior to registration

Major surgery ≤ 3 weeks prior to registration

Cannot have received: radiation therapy

Exception: ≤ 2 weeks prior to registration

Radiation therapy ≤ 2 weeks prior to registration

Lab requirements

Blood counts

Hemoglobin ≥ 9.0 g/dL; ANC ≥ 1500/mm^3; Platelet count ≥ 100,000/mm^3

Kidney function

Calculated creatinine clearance ≥ 45 ml/min using the Cockcroft-Gault formula

Liver function

Total bilirubin ≤ 1.5 x ULN; ALT and AST ≤ 3 x ULN (≤ 5 x ULN for patients with liver involvement)

Hemoglobin ≥ 9.0 g/dL (obtained ≤ 14 days prior to registration), no transfusions allowed ≤ 14 days prior to registration; ANC ≥ 1500/mm^3; Platelet count ≥ 100,000/mm^3; Total bilirubin ≤ 1.5 x ULN; ALT and AST ≤ 3 x ULN (≤ 5 x ULN for patients with liver involvement); Calculated creatinine clearance ≥ 45 ml/min using the Cockcroft-Gault formula

Structured fields extracted by AI. May contain errors — verify against the official protocol.

US trial sites

  • Mayo Clinic in Arizona · Scottsdale, Arizona

Showing up to 5 US sites. See all sites on ClinicalTrials.gov →

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