Results in 2nd and later-line Claudin 18.2-positive advanced gastric cancers versus investigator’s choice of therapy. The trial included patients with locally advanced or metastatic gastric cancer, gastroesophageal junction (GEJ) cancer, or esophageal adenocarcinoma (EAC) with Claudin 18.2 (CLDN18.2) expression on at least 25% of tumor cells at any staining intensity.

The trial had dual primary endpoints of OS in 3rd and later-line treatment and progression-free survival (PFS) in the overall trial population. The trial met the dual primary endpoint of OS in 3rd and later-line treatment, and a key secondary endpoint of OS in the overall trial population of patients treated in the 2nd and later-line setting, demonstrating a statistically significant and highly clinically meaningful improvement.

For the other dual primary endpoint of PFS as assessed by blinded independent central review (BICR), results showed a trend toward improved PFS in patients treated in the 2nd and later-line setting but did not reach statistical significance.

The majority of patients with gastric/GEJ cancers are diagnosed at an advanced or metastatic stage, where the prognosis is especially poor and treatment options are limited, with less than 20% surviving more than one year.1,2 CLDN18.2 has emerged as an important therapeutic target for these patients, with an estimated 60% of gastric/GEJ cancers expressing CLDN18.2 in 25% or more of tumor cells.3 Each year, there are roughly 183,500 patients in the US, EU, China and Japan treated in the 2nd and later-line setting for advanced or metastatic CLDN18.2-positive, non-HER2-positive gastric/GEJ cancers.4

Rui-Hua Xu, M.D., Ph.D., Professor in the Department of Medical Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, China, and principal investigator of the trial said: "Metastatic gastric cancer is an aggressive disease with very limited options once patients progress after first-line treatment. Sone-Ve is the first CLDN18.2-targeted antibody drug conjugate to demonstrate an overall survival benefit in this setting and has the potential to establish a new precision treatment for a broader population of patients with CLDN18.2 expression."

Susan Galbraith, Executive Vice President, Oncology Haematology R&D, said: "Sone-Ve has the potential to reshape the treatment of gastric cancer by replacing classic chemotherapy with this novel targeted antibody drug conjugate to improve outcomes for patients. These transformative results from the first Phase III readout for Sone-Ve, together with our broad development program, highlight the potential for Sone-Ve to become an important new medicine in CLDN18.2-positive cancers."

Sone-Ve was well tolerated, and its profile was consistent with the known safety profile of Sone-Ve with no new safety signals identified.

Sone-Ve is a potential global first-in-class CLDN18.2-targeting antibody drug conjugate (ADC) with a monomethyl auristatin E (MMAE) payload.

These data will be presented at a forthcoming medical meeting and shared with global regulatory authorities.

Sone-Ve has received Orphan Drug Designation from the US Food and Drug Administration and the European Commission for the treatment of gastric and GEJ cancers. It has also received Breakthrough Designation in China for the 2nd-line treatment of gastric cancer.