OncoMatch/Clinical Trials/NCT06515470
Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of BTX-9341 in Advanced and/or Metastatic Breast Cancer
Is NCT06515470 recruiting? Yes, currently enrolling (May 2026). This Phase 1 trial studies multiple treatments including BTX-9341 and Fulvestrant for breast cancer.
Treatment: BTX-9341 · Fulvestrant · BTX-9341 — The purpose of this study is to test BTX-9341 alone or in combination with fulvestrant (a currently marketed medication for breast cancer) in participants with advanced and/or metastatic hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer. The study includes a dose escalation part (Part A) where small groups of participants will receive increasing doses of BTX-9341 or BTX-9341 + fulvestrant followed by a dose expansion part (Part B) where participants will receive the dose of BTX-9341 selected in Part A + fulvestrant.
Check if I qualifyExtracted eligibility criteria
Cancer type
Breast Carcinoma
Biomarker criteria
Excluded: RB1 mutation
Prior therapy
Must have received: CDK4/6 inhibitor — dose escalation: any; dose expansion: at most 2 lines (1 adjuvant, 1 metastatic), at least 6 months duration
received CDK4/6 inhibitor therapy (dose escalation); received at most 2 lines of CDK4/6 inhibitor therapy (1 in the adjuvant setting and 1 in the metastatic setting) and must have been on prior CDK4/6 inhibitor therapy for at least 6 months (dose expansion)
Lab requirements
Blood counts
ANC ≥ 1500 per mL (no growth factors allowed); Platelet count ≥ 100,000 per mL (no transfusions or thrombopoietic agents allowed); Hemoglobin ≥ 9.0 g/dL (packed red blood cell transfusion allowed up to 14 days prior to trial entry)
Liver function
Bilirubin ≤ 2.0 × institutional ULN (or < 3.0 × institutional ULN if Gilbert's disease is present); ALT/AST ≤ 3.0 × institutional ULN (≤ 5.0 × institutional ULN if liver metastases present); Alkaline phosphatase ≤ 2.5 × institutional ULN (≤ 5.0 × institutional ULN if bone or liver metastases present)
Acceptable hematologic function: ANC ≥ 1500 per mL. Platelet count ≥ 100,000 per mL. Hemoglobin ≥ 9.0 g/dL. Acceptable liver function: Bilirubin ≤ 2.0 × institutional ULN (or < 3.0 × institutional ULN if Gilbert's disease is present); ALT/AST ≤ 3.0 × institutional ULN (≤ 5.0 × institutional ULN if liver metastases present); Alkaline phosphatase ≤ 2.5 × institutional ULN (≤ 5.0 × institutional ULN if bone or liver metastases present)
Structured fields extracted by AI. May contain errors — verify against the official protocol.
US trial sites
- Biotheryx Investigative Site · Rochester, Minnesota
- Biotheryx Investigative Site · Omaha, Nebraska
- Biotheryx Investigative Site · Houston, Texas
- Biotheryx Investigative Site · San Antonio, Texas
- Biotheryx Investigative Site · West Valley City, Utah
Showing up to 5 US sites. See all sites on ClinicalTrials.gov →
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