Alphamab Oncology (Stock Code: 9966) and CSPC Pharmaceutical Group Limited (Stock Code: 1093) jointly announced that JSKN003, co-developed with the subsidiary Shanghai JMT-Bio Technology Co., Ltd., has received another Breakthrough Therapy Designation (BTD) from the Center for Drug Evaluation (CDE) for patients with HER2+ advanced colorectal cancer (CRC) who have progressed following oxaliplatin, fluorouracil, and irinotecan. In March 2025, JSKN003 obtained a similar BTD for platinum-resistant recurrent epithelial ovarian cancer (PROC).
CRC ranks among the most prevalent cancers globally, with more than 500,000 new cases annually in China and a growing incidence trend. Current therapy options have limited efficacy, and there is a significant unmet clinical need. Data presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting showed that, in a pooled analysis of 50 patients with HER2-overexpressing (IHC3+) advanced gastrointestinal tumors (including 23 CRC patients), JSKN003 monotherapy demonstrated an objective response rate (ORR) of 61.9%, a disease control rate (DCR) of 95.2%, a median progression-free survival (mPFS) of 13.77 months, and a median duration of response (mDoR) of 12.06 months among the CRC subgroup. Among 43 patients treated at the recommended Phase II dose, Grade 3 or higher treatment-related adverse events (TRAEs) occurred in 14.0% of patients, and no TRAEs led to treatment discontinuation or death.
JSKN003 is a biparatopic HER2-targeting antibody-drug conjugate (ADC) utilizing a topoisomerase I inhibitor linked to the N-glycosylation site of KN026 through a glycosite-specific conjugation. Alphamab Oncology licensed JSKN003 to Shanghai JMT-Bio Technology for development and commercialization in mainland China. Three Phase III clinical trials are in progress for HER2+ breast cancer, HER2-low breast cancer, and PROC.
Alphamab Oncology is a biopharmaceutical company in the People’s Republic of China with an integrated technology platform focusing on ADCs, bispecific antibodies, and protein engineering. One product has been approved by the National Medical Products Administration (NMPA), and multiple therapies are in Phase III or pivotal trials. The company has leveraged protein engineering platforms and molecular modeling expertise to develop new generations of multi-functional biological drug candidates.
A cautionary statement indicates that there is no guarantee of successfully developing or marketing JSKN003. The announcement was issued on October 20, 2025.