The Multicenter, Open-label, Single-arm, Multi-cohort Phase Ib/II Clinical Study to Evaluate the Efficacy and Safety of JSKN016 in Combination Therapy in Chinese Participants With Inoperable Locally Advanced or Metastatic HER2-negative Breast Cancer
This study aims to evaluate the safety and effectiveness of JSKN016 in combination with different treatments for patients with HER2-negative breast cancer that cannot be removed by surgery or has spread to other parts of the body. The study includes four groups of patients based on treatment history and tumor characteristics. Each group will receive JSKN016 with chemotherapy or immunotherapy. The goal is to find out how well the treatment works and how safe it is.
• Capable of understanding and signing the informed consent form.
• Aged ≥18 and ≤75 years, regardless of sex.
• Histologically or cytologically confirmed inoperable locally advanced or metastatic HER2-negative breast cancer.
• Hormone receptor-positive participants with progression/intolerance after standard endocrine therapy, or unsuitable for it.
• Disease progression confirmed by radiological evidence post-systemic treatment.
• Available archived or newly obtained tumor tissue/biopsy.
• No prior systemic therapy for advanced disease, except for prior endocrine ± targeted therapy or CDK4/6 inhibitors.
• Measurable non-CNS lesion per RECIST 1.1.
• Expected survival ≥3 months.
⁃ ECOG performance status of 0 or 1.
⁃ Contraceptive use agreement for fertile participants.
⁃ Adequate organ function within 7 days of enrollment:
∙ Bone marrow: ANC ≥1.5 × 10⁹/L, Hemoglobin ≥90 g/L, Platelets ≥100 × 10⁹/L.
‣ Liver: Bilirubin ≤1.5 × ULN, ALT/AST ≤3 × ULN.
‣ Renal: Creatinine ≤1.5 × ULN or Ccr ≥60 mL/min.
‣ Coagulation: INR/PT ≤1.5 × ULN, APTT ≤1.5 × ULN.
⁃ LVEF ≥50%.