Objective:To explore the clinical efficacy of apatinib combined with tirelizumab in the treatment of advanced gastric cancer patients who failed first-line chemotherapy, as well as its impact on peripheral blood tumor angiogenesis regulatory factor levels and long-term survival.Methods:A prospective study was conducted on 144 advanced gastric cancer patients who failed first-line chemotherapy and were admitted to the Handan Central Hospital from January 2020 to December 2021. They were divided into two groups using a random number table method, with 72 patients in each group. The control group was treated with tirezizumab alone, while the observation group was treated with apatinib combined with tirezizumab. After four consecutive courses of treatment, the short-term efficacy of both groups was observed. We compared the levels of serum tumor markers [carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199, CA724, CA125], tumor angiogenesis regulatory factors [vascular endothelial growth factor (VEGF), stromal cell-derived factor-1α (SDF-1 α), insulin-like growth factor-1 (IGF-1), matrix metalloproteinase-9 (MMP-9)], and quality of life scores between two groups before and after treatment. Long term follow-up was conducted on all patients, and the long-term survival status of two groups was statistically analyzed. Two groups of adverse reactions were compared.Results:The objective remission rate and disease control rate (51.39%, 80.56%) of the observation group were significantly higher than those of the control group (31.94%, 61.11%, all P<0.05). After treatment, the serum levels of CEA, CA199, CA724, CA125, VEGF, SDF-1α, IGF-1, and MMP-9 in both groups were significantly reduced compared with those before treatment (all P<0.05), and the observed group showed a more significant decrease in the above indicators (all P<0.05). After treatment, the scores of physical function, emotional function, social function, role function, and overall health status in the European Organization for Research and Treatment of Cancer Core Scale C30 were significantly higher than before treatment (all P<0.05), and the increase was more significant in the observation group (all P<0.05). The median progression free survival and median overall survival in the observation group were 5.9 months and 13.1 months, respectively, significantly longer than those in the control group (4.5 months and 9.6 months) (all P<0.05). During the treatment period, both groups experienced varying degrees of adverse reactions such as hypertension, leukopenia, thrombocytopenia, and liver and kidney damage, but both were mainly grade Ⅰ-Ⅱ. The overall adverse reactions were clinically controllable and tolerable by patients. The incidence of hypertension, thrombocytopenia, hand foot syndrome, and oral ulcers in the observation group was significantly higher than that in the control group (all P<0.05). Conclusions:The combination of apatinib and tirezizumab can effectively regulate the levels of peripheral blood tumor markers and angiogenic regulatory factors in advanced gastric cancer patients who have failed first-line chemotherapy, improve short-term anti-tumor efficacy, and bring more survival benefits to patients.