ALPHAMAB-B (09966): The latest research results of the Phase III clinical trial of KN026 will be presented at the 2025 ESMO conference in the form of an LBA oral presentation.

ALPHAMAB-B (09966) announced that the first interim analysis results of the Phase III clinical trial ("KN026-001," also known as KC-WISE) for the second-line and above treatment of HER2+ GC (including GEJ) with KN026 in combination with chemotherapy, developed in collaboration with the subsidiary of CSPC PHARMA Limited, Shanghai Jintiante Biotechnology Co., Ltd., have been presented in the form of an LBA oral report at the 2025 ESMO meeting. HER2+ GC/GEJ patients (experiencing disease progression after receiving treatment based on trastuzumab) were randomized to receive either KN026 in combination with chemotherapy (the anetumab ravtansine group) or placebo in combination with chemotherapy (control group). Patients were stratified based on (i) chemotherapy type, (ii) HER2 expression levels, and (iii) number of prior treatment lines. The baseline characteristics of the two groups of patients were generally balanced. The median age of the anetumab ravtansine group was approximately 64 years, while the control group was 61 years. Over 80% of patients in both groups had an ECOG PS score of 1, and almost all patients were diagnosed with stage IVB disease at enrollment. All patients had previously received chemotherapy, with taxane-based chemotherapy regimens being the most common (over 70%), while the remaining patients received regimens based on irinotecan. As of April 3, 2025, the median follow-up time was 9.7 months (95%CI: 7.2 to 11.9 months) for the anetumab ravtansine group and 9.8 months (95%CI: 7.4 to 12.9 months) for the control group. Conclusion: The interim analysis showed that compared to placebo in combination with chemotherapy, KN026 in combination with chemotherapy achieved clinically meaningful and statistically significant benefits in terms of PFS and OS and demonstrated good controllable safety characteristics. These results suggest that KN026 in combination with chemotherapy may be a promising new treatment option for HER2+ GC/GEJ patients who have experienced disease progression after previous treatment based on trastuzumab. KN026 aims to be a global next-generation HER2-targeted therapy. With its innovative structure, it can simultaneously bind to two different clinically validated HER2 epitopes (epitopes II and IV) while retaining the wild-type Fc region. This allows KN026 to (i) dual blockade of HER2-related signaling pathways, (ii) enhance binding to the HER2 receptor, (iii) reduce HER2 protein on the cell surface, and (iv) enhance tumor killing through complete antibody-dependent cell-mediated cytotoxicity. This binding mechanism makes KN026 exhibit excellent tumor-inhibiting effects. Currently, multiple Phase III clinical trials are ongoing in China, including KN026 in combination with albumin-bound paclitaxel for first-line treatment of HER2+ BC, KN026 in combination with chemotherapy for second-line and above treatment of HER2+ GC/GEJ, and KN026 in combination with albumin-bound paclitaxel for neoadjuvant treatment of BC.