Alphamab Oncology (stock code: 9966.HK) announced that anti-HER2 bispecific antibody-drug conjugate (ADC) JSKN003 has received approval from the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA) to initiate a Phase III clinical study (study number: JSKN003-306). The study aims to compare the efficacy of JSKN003 versus investigator-selected chemotherapy for the treatment of platinum-resistant recurrent epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer.

Ovarian cancer (OC) ranks as the third most common gynecologic malignancy in China and continues to show a rising incidence, with the highest mortality rate among all malignant gynecologic tumors. The standard treatment regimens recommended by authoritative guidelines both domestically and internationally include surgery combined with platinum-based chemotherapy and targeted therapy maintenance. However, about 70% of OC cases recur after treatment and progress to platinum-resistant ovarian cancer (PROC), leaving patients with limited effective treatment options and poor prognosis. The 2024 NCCN guideline recommend non-platinum cytotoxic drugs and targeted monotherapy as the preferred treatment option for patients with PROC. Previous studies have shown that the objective response rate (ORR) of PROC treated with non-platinum chemotherapy alone is only 4% to 13%, while the ORR for non-platinum chemotherapy combined with targeted therapy is merely 10% to 30%, highlighting an urgent need for new treatment options.

JSKN003 is an anti-HER2 bispecific ADC, which is developed inhouse with Alphamab's proprietary Glycan-specific conjugation platform. Multiple clinical studies of JSKN003 are currently being conducted in Australia and China. Clinical research results have demonstrated favorable tolerability and safety profile, with promising efficacy of JSKN003 in heavily pretreated patients with advanced solid tumors. Data from two Phase I clinical studies of JSKN003 for the treatment of PROC presented at the 2024 European Society for Medical Oncology (ESMO) Congress indicated that JSKN003 monotherapy showed promising efficacy signals in patients with advanced PROC, and the efficacy was observed across patients with or without HER2 expression, prior bevacizumab treatment, prior PARP inhibitor treatment, and whether they were primary platinum-resistant.

JSKN003-306 is a randomized, open-label, parallel-controlled, multi-center Phase III clinical study for the all-comer population with platinum-resistant recurrent epithelial ovarian cancer, primary peritoneal cancer, or fallopian tube cancer who have received 1-4 lines of prior treatment. The study aims to compare the efficacy and safety of JSKN003 versus investigator-selected chemotherapy in this patient population.