eligibility_summary
Adults (male/female) 18–75 with path-confirmed early/locally advanced, HER2-low breast cancer (IHC 1+ or 2+/ISH–), ECOG 0–1. LN+ allowed, if LN–: HR– (ER–/PR–) requires T≥2, HR+ (ER+ or PR+) requires T≥5. Exclude: stage IV, anti-tumor therapy/radiation in past 5 yrs (except cured cervical CIS, skin BCC/SCC), receiving other trial therapy, major non-breast surgery <4 wks or not recovered, prior ADCs, immunosuppressants, anti-HER2.
trial_source
clinical_trials.gov from Dec 2, 2025
annotation_status
ai
ai_summary
Interventions: Disitamab vedotin (RC48, anti‑HER2 antibody–drug conjugate with MMAE payload), 2 mg/kg q2w ×8, Tislelizumab (anti‑PD‑1 IgG4 monoclonal antibody), 200 mg IV q3w ×6, given as neoadjuvant therapy for early/high‑risk or locally advanced HER2‑low breast cancer. Mechanisms of action: Disitamab vedotin binds HER2 on tumor cells (effective even at low HER2), is internalized, then releases MMAE to disrupt microtubules, causing mitotic arrest and apoptosis, it can also trigger ADCC and bystander killing. Tislelizumab blocks the PD‑1 checkpoint to reinvigorate antitumor T‑cell responses, it is engineered to minimize Fcγ receptor binding on macrophages to reduce T‑cell clearance. Targets/pathways: HER2 on breast cancer cells, microtubule dynamics, PD‑1/PD‑L1 immune checkpoint on T cells and tumor/immune cells, effector CD8+ T cells and NK cell–mediated cytotoxicity.