The phase 3 COMPASSION-15 study, conducted across 75 clinical sites in China, confirmed that incorporating cadonilimab with chemotherapy provided significant survival benefits for patients with HER2-negative advanced gastric or gastroesophageal junction adenocarcinoma (G/GEJA) as a first-line treatment, compared to chemotherapy alone (Shen et al., 2025). Here, ERBB2 is linked to gastroesophageal junction adenocarcinoma.