Alphamab Oncology (stock code: 9966.HK) announced that the Investigational New Drug (IND) application for JSKN021, an independently developed innovative dual payload bispecific antibody-drug conjugate (ADC) targeting EGFR and HER3, has been officially accepted by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA). The Company plans to initiate a clinical study of JSKN021 for the treatment of advanced malignant solid tumors.

JSKN021 is a "2-in-1" dual payload bispecific ADC targeting EGFR and HER3. By leveraging glycan-specific conjugation technology, it precisely and quantitatively links two different cytotoxic payloads to the antibody's Fc region. This process has been refined to be simple, stable, and highly efficient. The generated ADC product demonstrates the characteristically high stability and safety profile intrinsic to Alphamab Oncology's proprietary technology platforms. According to preclinical data presented at the 2025 annual meeting of American Association for Cancer Research (AACR), JSKN021 inhibited the growth of cancer cells with either HER3 or EGFR or both expressions. Furthermore, JSKN021 showed stronger tumor inhibition efficacy than mono payload ADCs in multiple CDX models.

This Phase I clinical study will evaluate the safety, tolerability, pharmacokinetics (PK), and antitumor activity of JSKN021 in patients with advanced malignant solid tumors, and determine the maximum tolerated dose (MTD) and/or recommended Phase II dose (RP2D).