Hansoh Pharma Presents Positive Phase 2 Study Findings for HS-20089 in Platinum-Resistant Ovarian Cancer

Strategic Insights -

HS-20089, a B7-H4-targeted antibody-drug conjugate developed by Hansoh Pharma, has demonstrated promising efficacy in heavily pretreated patients with platinum-resistant ovarian cancer (PROC). The phase 2 study found a confirmed objective response rate (ORR) of 48.5%, a median duration of response (DoR) of 6.8 months, a median progression-free survival (mPFS) of 6.4 months, and a median overall survival (mOS) of 14.6 months.

Key Takeaways:

  • The phase 2 study evaluated the efficacy and safety of HS-20089 in patients with PROC who had received a median of 3 prior lines of anti-tumor therapy.
  • HS-20089 showed a confirmed ORR of 48.5% in patients with high-grade serous ovarian cancer, with a DoR of 6.8 months.
  • The median PFS for HS-20089 was 6.4 months, and the median OS was 14.6 months at a dose of 4.8mg/kg.
  • HS-20089 demonstrated a manageable safety profile, with no new safety signals observed.
  • The study results support further development of HS-20089 in patients with PROC, and a phase 3 study is ongoing.
  • The inclusion of patients not selected based on tumor B7-H4 expression levels highlights the potential of HS-20089 as a treatment option for PROC regardless of B7-H4 expression.
  • HS-20089 has shown promising efficacy in heavily pretreated patients with PROC, addressing the urgent need for more effective treatment approaches.
  • The ongoing phase 3 study will further evaluate the efficacy and safety of HS-20089 in patients with PROC.

Statistics:

  • Confirmed ORR: 48.5%
  • DoR: 6.8 months
  • Median PFS: 6.4 months
  • Median OS: 14.6 months at 4.8mg/kg
  • Dose escalation not indicated for PFS and OS
  • 35 patients with high-grade serous ovarian cancer were enrolled in the study
  • 72.7% of patients had been treated with bevacizumab, and another 72.7% had received a PARP inhibitor

Sources:

  • Hansoh Pharmaceutical Group Co., Ltd. (Original Press Release)
  • ESMO 2025 Annual Meeting
  • International Agency for Research on Cancer (Global Cancer Observatory)
  • Pujade-Lauraine E, et al. (Lancet Oncol. 2021)
  • Moore KN, et al. (N Engl J Med. 2023)
  • Hansoh Pharma. (About HS-20089)
  • Hansoh Pharma. (About Ovarian Cancer)
  • Hansoh Pharma. (About ESMO)
  • Hansoh Pharma. (About Hansoh Pharma)