AstraZeneca PLC announced today that its potential first-in-class CLDN18.2-targeting antibody-drug conjugate, Sone-Ve, has met its primary endpoint in the Phase III CLARITY-Gastric01 trial. Compared to the investigator's choice of treatment, Sone-Ve demonstrated a statistically significant and highly clinically meaningful improvement in overall survival for patients with CLDN18.2-positive advanced gastric cancer in the second-line and later settings.

The trial enrolled patients with locally advanced or metastatic gastric cancer, gastroesophageal junction cancer, or esophageal adenocarcinoma, requiring at least 25% CLDN18.2 expression in tumor cells. The study achieved one of its dual primary endpoints—overall survival in the third-line and later treatment setting. Additionally, a key secondary endpoint—overall survival in the overall second-line and later population—also showed a significant improvement. However, the other primary endpoint, progression-free survival, showed a trend toward improvement but did not reach statistical significance.

In terms of safety, Sone-Ve was well tolerated, with a profile consistent with its known safety characteristics, and no new safety signals were identified. CLDN18.2 has become an important therapeutic target in gastric cancer, as approximately 60% of gastroesophageal cancer patients express this protein in their tumor cells. The prognosis for advanced gastric cancer patients is extremely poor, with a median survival of only 5 to 9 months after progression on first-line therapy.

AstraZeneca PLC's Executive Vice President of Oncology R&D, Susan Galbraith, stated that Sone-Ve has the potential to reshape the treatment landscape for gastric cancer by replacing traditional chemotherapy with a novel targeted ADC. Detailed data will be presented at an upcoming medical conference and submitted to regulatory authorities.