eligibility_summary
Eligibility: Adults (≥18) with pathology-confirmed HER2‑negative breast cancer (IHC 0/1+ or 2+ ISH−) and a measurable brain lesion. Exclusions: leptomeningeal disease, acute/subacute hemorrhagic mets, inadequate organ function (low ANC/PLT/Hb, high TBIL/ALT/AST), serious comorbidities (allergy, immunodeficiency incl HIV), pregnant/lactinating or no contraception, unable to undergo contrast MRI, prior sacituzumab govitecan resistance, investigator deems unsuitable.
trial_source
clinical_trials.gov from Dec 2, 2025
annotation_status
ai
ai_summary
Phase II, single-arm trial in HER2-negative breast cancer brain metastases testing sacituzumab govitecan (Trodelvy) plus head radiotherapy. Sacituzumab govitecan is an antibody-drug conjugate: a humanized anti–Trop-2 IgG linked to SN-38 (active irinotecan metabolite), a cytotoxic topoisomerase I inhibitor. Mechanism: the antibody binds Trop-2 on tumor cells, internalizes, and releases SN-38 to block DNA religation during replication, causing DNA damage/apoptosis (with a bystander effect). Radiotherapy (focal or whole-brain) delivers ionizing radiation to induce DNA double-strand breaks and tumor cell death. Targets/pathways: Trop-2–expressing breast cancer cells in brain metastases, DNA replication/repair pathways (Topo I) and radiation-induced DNA damage responses.