November 10, 2025
Hansoh Pharmaceutical Group Co., Ltd. (Hansoh Pharma, 03692.HK) today announced that positive Phase 2 results of HS-20089 (licensed to GSK as GSK5733584), a B7-H4-targeted antibody-drug conjugate (ADC), in platinum-resistant ovarian cancer (PROC) were presented as an oral presentation at the 2025 International Gynecologic Cancer Society (IGCS) Annual Global Meeting (November 5–7, Cape Town South Africa.). The findings were first presented at the 2025 European Society for Medical Oncology (ESMO) Annual Meeting.
Details of the Oral Presentation are as follows:
As of the June 20, 2025 data cutoff, HS-20089 is the first B7-H4 ADC to demonstrate promising efficacy in heavily pretreated patients with platinum-resistant ovarian cancer (PROC) who were not selected based on tumor B7-H4 expression. It showed a confirmed ORR of 48.5% and DoR of 6.8 months, a mPFS of 6.4 months and a mOS of 14.6 months. The efficacy was analyzed in all patients who received treatment, with a median follow-up time of 11.5 months. The safety profile of HS-20089 was consistent with data from the phase 1 study, with no signals of interstitial lung disease observed. These clinical results support the further development of HS-20089 in patients with PROC and a phase 3 study is on-going (NCT06855069).
For more study results details：//www.hspharm.com/news/news-detail-513373.htm.
About HS-20089
HS-20089 is a B7-H4-targeted ADC self-developed by Hansoh Pharma. As of now, HS-20089 has entered phase III clinical research for the treatment of the platinum–resistant ovarian cancer indication in China and currently is also undergoing PoC clinical studies for the treatment of endometrial cancer and other solid tumors.
In October,2023, Hansoh Pharma entered into an exclusive license agreement with GlaxoSmithKline Intellectual Property (No.4) Limited (“GSK”), granting GSK an exclusive worldwide license (excluding the Chinese Mainland, Hong Kong, Macau, and Taiwan) to develop, manufacture and commercialize the Product（also known as GSK5733584）. GSK is advancing GSK5733584 through a global development programme, with Phase I trials underway globally that includes the BEHOLD-1 (NCT06431594) and BEHOLD-2 (NCT06796907) studies.
In May 2025, HS-20089 was approved by the NMPA as a Breakthrough-Therapy-Designated Drug, with the proposed indication for platinum-resistant recurrent epithelial ovarian cancer, fallopian tube cancer, or primary peritoneal cancer.
About Ovarian Cancer
Ovarian cancer (OC) is one of the most prevalent gynecological malignancies. In 2022, approximately 324,603 new cases of ovarian cancer were diagnosed worldwide, making it the eighth most common malignancy among women. With around 206,956 deaths that year, ovarian cancer was the eighth leading cause of cancer-related mortality among female patients. In China, the incidence in 2022 was 61,060, with a mortality of 32,646[1].
The current standard treatment for ovarian cancer involves surgery combined with platinum-based chemotherapy. However, most advanced-stage patients relapse within 3 years and eventually develop drug resistance to platinum-based chemotherapy. The clinical treatment methods and efficacy for platinum-resistant recurrent ovarian cancer (PROC) remain extremely limited.
Recent Phase III randomized controlled trials show that the ORR for non-platinum monotherapy chemotherapy is 4%–15.9%, with a median PFS of 3.4–3.98 months. In patients who have received 1–2 lines of prior treatment, non-platinum chemotherapy combined with bevacizumab yields an ORR of 27.3%, extending the median PFS to 6.7 months and the median OS to 16.6 months. Despite a significant extension in PFS, no notable OS benefit is observed compared to non-platinum chemotherapy[2-6].This disease represents a major unmet clinical need, underscoring the urgent demand for more effective treatment approaches.
About IGCS 2025
As the first ever global IGCS meeting to be held on the African continent, IGCS 2025 in Cape Town offers a unique opportunity to engage with leading experts in all disciplines involved in gynecologic oncology from around the world. The conference will provide cutting-edge research presentations, collaborative workshops, and educational sessions aimed at enhancing your clinical practice and women's cancer care globally.
References
[1]International Agency for Research on Cancer. (2024). Cancer TODAY: GLOBOCAN 2022 (version 1.1). Retrieved April 26, 2025, from Global Cancer Observatory
[2]Pujade-Lauraine E, Fujiwara K, Ledermann JA, et al. Lancet Oncol. Jul 2021;22(7):1034-1046.
[3] Gaillard S, Oaknin A, Ray-Coquard I, et al. Gynecol Oncol. Nov 2021;163(2):237-245.
[4] Hamanishi J, Takeshima N, Katsumata N, et al. J Clin Oncol. Nov 20 2021;39(33):3671-3681.
[5] Pujade-Lauraine E, Hilpert F, Weber B, et al.
[6] Moore KN, Angelergues A, Konecny GE, et al. N Engl J Med. Dec 7 2023;389(23):2162-2174.
