China-based Sihuan Pharmaceutical Holdings Group Ltd (HKG: 0460) has announced that it has received clinical trial approval from the National Medical Products Administration (NMPA) for its XZP-KM501 (KM501) in solid tumors with HER2 positive, middle to low-expression. This marks a significant step forward in the development of innovative treatments for HER2-related cancers.
KM501: A First-of-Its-Kind HER2/HER2 Double Epitope ADC
KM501 is an in-house developed HER2/HER2 double epitope bispecific antibody-drug conjugate (ADC). It is the first of its kind to be filed for patent protection in China. The antibody uses a common light chain model and incorporates internationally leading patented technology for the removal of fucose, with independent intellectual property rights. It targets both trastuzumab (anti-HER2 domain IV) and patstuzumab (anti-HER2 domain II) epitopes, enhancing endocytosis and increasing toxin accumulation at the target site, thereby creating strong anti-tumor activity in tumors with low HER2 expression.
Comparative Efficacy and Potential
In various tumor mouse models, KM501 demonstrated better or comparable tumor inhibition ability to Enhertu (DS-8201), showcasing its potential as a best-in-class treatment option. This development is particularly significant given the prevalence of HER2 low expression in breast cancer, the most common malignant tumor among women. According to the World Health Organization (WHO), breast cancer was diagnosed in 420,000 people in China in 2020, with about 50% being HER2 low expression.-Fineline Info & Tech
