A Study of Paclitaxel Combined With Apatinib and Adebrelimab in Gastric/Gastroesophageal Junction Adenocarcinoma

Inclusion Criteria: * 1\) Age: 18 \~ 75 years old, male and female; * 2\) ECOG score: 0 or 1; * 3\) Patients with unresectable locally advanced or metastatic gastric cancer/gastroesophageal junction adenocarcinoma confirmed by histopathology; * 4\) Patients who have received at least first-line immunotherapy progression or intolerance in the past, and the number of previous systemic treatment lines does not exceed 2 lines; The best curative effect of frontline containing PD-1/PD-L1 was CR, PR or SD; * 5\) According to the evaluation criteria for the efficacy of solid tumors (RECIST 1.1), there should be at least one measurable lesion that has not received local treatment such as radiotherapy (lesions located in the area of previous radiotherapy can also be selected as target lesions if progression is confirmed); * 6\) The major organs function normally and meet the following criteria * a. In the past 14 days without the use of granulocyte colony-stimulating factor, the absolute value of neutrophil (ANC) ≥1.5x109 /L; * b. Platelets ≥100×109 /L in the past 14 days without blood transfusion; * c. Hemoglobin \>90g/L in the last 14 days without blood transfusion or use of erythropoietin; * d. Total bilirubin ≤1.5× upper limit of normal (ULN); * e. aspartate aminotransferase (AST), alanine aminotransferase (ALT) in ≤2.5×ULN (ALT or AST ≤5×ULN for patients with liver metastasis); * f. Serum creatinine ≤1.5×ULN and creatinine clearance (calculated by Cockcroft-Gault formula) ≥40 ml/min; * g. Good coagulation function, defined as International standardized ratio (INR) or prothrombin time (PT) ≤1.5 times ULN; * h. The myocardial enzyme profile is within the normal range (if the researchers comprehensively judge that the simple laboratory abnormality is not clinically significant, it is also allowed to be included); * 7\) Expected survival ≥3 months; * 8\) Women of reproductive age should agree to use contraceptives (such as Iuds, contraceptives, or condoms) during the study period and for 6 months after the study ends; Have a negative serum or urine pregnancy test within 7 days prior to study enrollment and must be a non-lactating patient; Men should consent to patients who must use contraception during the study period and for 6 months after the end of the study period; * 9\) Sign informed consent. Exclusion Criteria: * 1\) Patients who have previously received paclitaxel chemotherapy; Patients with neoadjuvant or adjuvant treatment with taxoid drugs and disease progression more than 6 months after the last chemotherapy were excluded; * 2\) HER2-positive patients; * 3\) Patients who are taking immunosuppressants or systemic hormone therapy for immunosuppressive purposes (dose \>10mg/ day prednisone or other therapeutic hormone) and continue to use within 2 weeks before enrollment; * 4\) Patients with severe liver and kidney insufficiency or heart insufficiency; * 5\) have multiple factors that affect oral drugs (such as inability to swallow, gastrointestinal resection, chronic diarrhea, and intestinal obstruction); * 6\) Patients with brain metastases accompanied by symptoms or symptom control for less than 3 months; * 7\) Patients who are known to be allergic to any investigational drug or drug excipient; * 8\) Pregnant or lactating female patients; * 9\) Patients who underwent major surgical procedures (craniotomy, thoracotomy, or laparotomy) or had unhealed surgical wounds, ulcers, or fractures within 4 weeks prior to initial dosing, except for patients ≥2 weeks after surgery and patients with old fractures that the investigator determined could be treated with the study drug; * 10\) Patients with moderate to severe ascites accompanied by clinical symptoms requiring repeated drainage; Patients with uncontrolled or clinical symptoms of pleural effusion or pericardial effusion; * 11\) Patients with clinically significant electrolyte disorders; * 12\) People with acute or chronic active hepatitis B or hepatitis C: hepatitis B virus (HBV) DNA \> 2000IU/ml or 104 copies /ml; Hepatitis C virus (HCV) RNA \> 103 copies /ml; Hepatitis B surface antigen (HbsAg) and anti-HCV antibody positive patients; * 13\) Patients with central nervous system metastasis, but with no clinical symptoms or accompanied by clinical symptoms after treatment, disease control and stable time ≥4 weeks can be enrolled; To meet the need for measurable lesions outside the central nervous system, hormone therapy should be discontinued 14 days before the first study of medication * 14\) Any life-threatening bleeding event within the previous 3 months, including patients requiring transfusion therapy, surgery or local therapy, and ongoing medication; * 15\) Patients with a history of arteriovenous thromboembolism events, including myocardial infarction, unstable angina pectoris, cerebrovascular accident or transient ischemic attack, pulmonary embolism, deep vein thrombosis, or any other severe thromboembolism within the past 6 months. The exception is implantable intravenous infusion port or catheter-derived thrombosis, or superficial venous thrombosis, which is stable after conventional anticoagulant therapy. Allow patients to prophylactically use small doses of low molecular weight heparin (e.g., enoxaparin 40 mg/ day); * 16\) Uncontrolled hypertension, systolic blood pressure \> 160 MMHG or diastolic blood pressure \> 100mmHg after optimal medical treatment, hypertensive crisis or hypertensive encephalopathy history; * 17\) Symptomatic congestive heart failure (New York Heart Association Grade II-IV). Symptomatic or poorly controlled arrhythmia. Patients with a history of congenital long QT syndrome or a QTc \> 500ms (calculated using the Fridericia method) corrected at screening; * 18\) For patients who received radiation therapy more than 4 weeks before the first treatment, all of the following conditions must be met to be enrolled: there is no current toxic reaction related to radiation therapy, no need to take glucocort