eligibility_summary
Eligible: women 18–70 with HER2+ breast cancer, metastatic or unresectable recurrence, measurable ≥1 cm, no prior 1st‑line anti‑HER2 for MBC, effective (neo)adjuvant anti‑HER2 ended >12 mo, ECOG 0–2, adequate marrow/organ, LVEF≥50, nonpregnant, contraception, consent. Exclude: symptomatic CNS mets (treated/stable OK), bone/skin‑only, major cardiac/GI/hepatic/viral/HIV disease, uncontrolled effusions, recent trial/major surgery, early relapse, ≥grade 3 neuropathy, drug allergy, pregnancy/lactation.
trial_source
clinical_trials.gov from Dec 2, 2025
annotation_status
ai
ai_summary
Trial NCT06641544 tests two first-line regimens for HER2-positive metastatic breast cancer: A) Inetetamab (anti-HER2 IgG1 monoclonal antibody) + Pertuzumab (anti-HER2 monoclonal antibody) + physician’s-choice chemotherapy, B) Inetetamab + Pyrotinib (irreversible pan-ErbB small-molecule TKI) + chemotherapy. Mechanisms: Inetetamab binds HER2 extracellular domain IV, inhibiting receptor phosphorylation and downstream signaling. Pertuzumab binds extracellular domain II, blocking HER2 dimerization, together they provide dual extracellular blockade. Pyrotinib binds the intracellular kinase domain, competing with ATP to block HER2 autophosphorylation, with Inetetamab it delivers extracellular + intracellular dual inhibition. Targets/pathways: HER2-overexpressing tumor cells, HER2 dimerization and kinase activity, downstream PI3K/AKT and MAPK pathways.