Clinical Trial

A Phase 3, Randomized, Multi-center, Open-label Study of DB-1303 Versus Investigator’s Choice Chemotherapy in Human Epidermal Growth Factor Receptor 2 (HER2)-low, Hormone Receptor Positive (HR+) Metastatic Breast Cancer Patients whose Disease has Progressed on Endocrine Therapy (ET) (DYNASTY-Breast02)

MOA: DB-103 is a HER2- targeting ADC with a DNA topoisomerase I inhibitor (P1003) payload

Key Eligibility Criteria:

• Pathologically documented advanced/metastatic BC
  • HER2-low (IHC1+ or IHC2+/ISH-) as determined by central lab
  • Never previously reported as HER2-positive
  • Documented as HR+ (ER and/or PgR ≥1%)
  • Adequate tumor tissue sample for HER2 assessment by central lab
• Disease progression on ET + CDK4/6 inhibitor w/in 6 months of starting 1L or on at least 2 lines of ET with or without targeted therapy
• No prior chemotherapy for mBC
• Previous treatment with anti-HER2 therapy or with ADC comprising an exatecan derivative excluded