This phase Ib study enrolled patients with previously untreated, unresectable, locally advanced or recurrent/metastatic HER2-negative GC/GEJ AC. Pts received IBI110 200mg IV Q3W and sintilimab 200mg IV Q3W plus XELOX...The disease control rate (DCR) was 94.1% (95% CI, 71.3-99.9). With a median follow up of 13.1 months (95% CI, 7.1-NC), the median duration of response (DoR) and progression-free survival (PFS) were 11.6 months (95% CI, 2.5-14.4) and 12.9 months (95% CI, 3.8-15.8), respectively.IBI110 in combination with sintilimab and XELOX demonstrated manageable safety and encouraging efficacy results in patients with first-line gastric adenocarcinoma.