Antengene’s ATG-022 (CLDN18.2 ADC) granted Breakthrough Therapy Designation for the treatment of gastric/gastroesophageal junction adenocarcinoma

CAR-T Digest - August 2020

Weekly Digest - August 2025

19 August 2025: Antengene’s ATG-022 (CLDN18.2 ADC) granted Breakthrough Therapy Designation for the treatment of gastric/gastroesophageal junction adenocarcinoma

Antengene’s CLDN18.2-targeting ADC ATG-022 received Breakthrough Therapy Designation from China’s NMPA for previously treated CLDN18.2-positive, HER2-negative gastric or gastroesophageal junction cancer, following earlier FDA Orphan Drug Designations in gastric and pancreatic cancers
In the CLINCH Phase 1/2 study, ATG-022 showed strong antitumor activity with ORR of 33–40%, DCR up to 90%, and multiple CRs, with efficacy seen even in very low CLDN18.2 expression (<5%)
Three patients achieved complete responses across different expression cohorts, underscoring its potential as a broad-spectrum CLDN18.2 therapy compared to other targeted treatments
The drug is in Phase 2 dose-expansion trials in China and Australia, with development strategies across first-line (with pembrolizumab plus chemo), second-line (with pembrolizumab), and third-line (monotherapy) gastric cancer treatment
Beyond gastric cancer, ATG-022 also showed tumor shrinkage in gynecologic tumors, with all seven evaluated patients responding, supporting its promise across multiple CLDN18.2-positive tumor types