Antengene Corporation Limited announced that China National Medical Products Administration (NMPA) has approved the Phase I study of ATG-022 for the treatment of advanced or metastatic solid tumors (the CLINCH Trial). The primary objective of the study is to evaluate the safety and tolerability of ATG-022 and to determine important dosing parameters including biologically effective dose, maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D) of ATG-022 monotherapy. ATG-022 is an antibody-drug-conjugate targeting Claudin 18.2. Claudins are cell adhesion molecules normally expressed within the tight junctions between cells to form a barrier that regulates cell permeability.

In cancer, Claudins are expressed at the cell surface due to changes in cell polarity. The Claudin 18.2 isoform is overexpressed in various primary malignant tumors including gastric, esophageal and pancreatic cancers. Data from preclinical studies, including results from gastric cancer-patient derived xenograft models presented at the 2022 American Association for Cancer Research (2022 AACR), showed that ATG-022 binds to Claudin 18.2 with low nanomolar affinity and demonstrated potent in vitro and in vivo antitumor effects, with in vivo efficacy observed in Claudin 18.2 low expression models.

This could pave the way for broad clinical utility of ATG-022 in gastric cancer patients with a wide range of Claudin 18.2 expression levels. ATG-022 demonstrated an excellent safety profile in Good Laboratory Practice (GLP) toxicology studies.