ANTENGENE-B (06996) has announced that its Investigational New Drug application for ATG-022 has been approved by the Center for Drug Evaluation (CDE) of China's National Medical Products Administration. The approval grants permission to initiate the pivotal Phase III CLINCH-3 study evaluating ATG-022, a Claudin 18.2 (CLDN18.2)-targeting antibody-drug conjugate, for the treatment of CLDN18.2-positive advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma.

The CLINCH-3 study is anticipated to commence initially in China and is planned as a multi-regional clinical trial. It is designed as a randomized, controlled, open-label, multicenter Phase III study. Its objective is to assess the efficacy and safety of ATG-022 compared to an investigator's choice of therapy in patients with CLDN18.2-positive advanced gastric or GEJ adenocarcinoma. As a key registration study, CLINCH-3 aims to support a future marketing authorization application for ATG-022 as a monotherapy for this patient population.

The primary endpoints of the study are progression-free survival and overall survival, both to be assessed by an independent review committee. Secondary endpoints include objective response rate, duration of response, disease control rate, safety, and other metrics. The company notes that there is no guarantee ATG-022 will ultimately be successfully developed or commercialized.