eligibility_summary
Eligible: adults >=18 with HER2+ invasive breast cancer, histologically proven mets (>=1), ER status known, oligometastatic (<=5 lesions, clustered nodes=1, exclude pleuritis carcinomatosa, miliary/peritoneal spread), measurable by RECIST 1.1, WHO PS 0-1, DFI >=24 mo if recurrent, staging PET-CT and MRI (breast/brain, liver or spine/pelvis if indicated). Exclude: prior metastatic therapy (except curative endocrine/radiation), CNS/leptomeningeal mets, unrelieved obstruction/compression, other active malignancy.
trial_source
clinical_trials.gov from Dec 2, 2025
annotation_status
ai
ai_summary
Intervention: Trastuzumab deruxtecan (T-DXd), an anti-HER2 antibody–drug conjugate (humanized IgG1 trastuzumab linked via a cleavable linker to a membrane‑permeable topoisomerase I inhibitor payload, DXd). Mechanism: Binds HER2/ERBB2 on tumor cells, partially blocks HER2 signaling and engages Fc-mediated ADCC, after internalization the linker is cleaved to release DXd, which inhibits topoisomerase I, causing DNA damage/apoptosis and a bystander effect to adjacent tumor cells. Targets: HER2‑positive breast cancer cells in oligometastatic disease, key pathways include HER2/ERBB signaling and DNA replication/repair via topo I. Design note: Single-arm Phase 2, T-DXd 5.4 mg/kg IV every 3 weeks for 16 cycles (8 neoadjuvant, local therapy, then 8 adjuvant).