eligibility_summary
Adults ≥18 with unresectable, histologically confirmed HER2+ cholangiocarcinoma or gallbladder cancer, ECOG 0–1, measurable disease, adequate organs, controlled HBV/HCV, contraception. Exclude >4 prior systemic cycles or prior PD‑1/PD‑L1/CTLA‑4, recent RT/live vaccine/investigational use, immunodeficiency or steroids, active CNS mets, autoimmune disease, pneumonitis, infection, LVEF<55%, severe hypersensitivity, transplant, pregnancy, serious comorbidity.
trial_source
clinical_trials.gov from Dec 2, 2025
annotation_status
ai
ai_summary
Phase II single-arm trial in previously untreated, unresectable HER2-positive cholangiocarcinoma/gallbladder cancer tests gemcitabine/cisplatin + trastuzumab + pembrolizumab. Mechanisms: Gemcitabine (antimetabolite, cytidine analog) blocks DNA synthesis, cisplatin (platinum chemotherapy) forms DNA crosslinks causing apoptosis, trastuzumab (anti-HER2 monoclonal antibody) inhibits HER2/ErbB2 signaling and mediates ADCC, pembrolizumab (anti–PD-1 monoclonal antibody) releases T-cell inhibition. Targets: HER2-overexpressing tumor cells, HER2–PI3K/AKT/MAPK pathway, DNA replication/repair, PD-1 checkpoint on T cells.