Fruquintinib and Albumin-paclitaxel Combined With or Without PD-1 Antibody in 2nd-line Treatment of G/GEJ Adenocarcinoma

To explore the efficacy and safety of fruquintinib and albumin-paclitaxel combined with or without PD-1 antibody in the second-line treatment of advanced gastric/gastroesophageal junction adenocarcinoma that failed to be treated by anti-PD-1 /PD-L1 regimen

Inclusion Criteria: 1. Have fully understood the study and voluntarily signed the informed consent; 2. Age ≥18 years old; 3. Pathologically confirmed advanced gastric/gastroesophageal junction adenocarcinoma with at least one systemic treatment; 4. Frontline experienced exposure to immune drugs (including exposure to PD-1 drugs in the neoadjuvant, adjuvant, and systemic treatment stages; For patients with metastasis and recurrence within 6 months after the end of adjuvant/neoadjuvant system treatment, the above-mentioned treatment is first-line treatment); 5. ECOG's physical condition was 0-1, and did not deteriorate within 7 days; 6. BMI≥18; 7. Expected survival ≥3 months; 8. The functions of vital organs meet the following requirements (the use of any blood components and cell growth factors is not allowed within the first 14 days of enrollment) a) Absolute neutrophil count ≥1.5×109/L, white blood cell ≥4.0×109/L; b) Platelet ≥100×109/L; c) Hemoglobin ≥90g/L; d) Total bilirubin TBIL≤1.5 times ULN; e)ALT and AST≤2.5 times ULN (up to 5 times in patients with liver metastasis); f) Urea/urea nitrogen (BUN) and creatinine (Cr) ≤1.5×ULN (and creatinine clearance (CCr) ≥ 50mL/min); g) Left ventricular ejection fraction (LVEF) ≥50%; h)Fridericia's corrected QT interval (QTcF) \30 mL within 3 months, accompanied by hematemesis, stool, and blood in the stool), hemoptysis (\>5 mL of fresh blood within 4 weeks), or thromboembolic events (including stroke events and/or transient ischemic attacks) within 12 months prior to enlistment; 15. Clinically significant cardiovascular disease, including but not limited to acute myocardial infarction, severe/unstable angina pectoris, or coronary artery bypass grafting within 6 months prior to enrollment; Congestive heart failure New York Heart Association (NYHA) Grade \>2; Ventricular arrhythmias requiring medical treatment; LVEF (left ventricular ejection fraction) \1×104 copies /mL or \>2000 IU/ml) must be excluded for a known hepatitis B virus (HBV) carrier; Known hepatitis C virus infection (HCV) and HCV RNA positive (\>1×103 copies /mL); 18. Unmitigated toxicity higher than CTCAE v5.0 grade 1 due to any previous anticancer therapy, excluding alopecia, lymphocytopenia, and oxaliplatin grade ≤2 neurotoxicity; 19. Women who are pregnant (positive pregnancy test before medication) or breastfeeding; 20. Received blood transfusion therapy, blood products and hematopoietic factors, such as albumin and granulocyte colony-stimulating factor (G-CSF), within 28 days before enrollment; 21. Any other medical condition, clinically significant metabolic abnormality, physical abnormality or laboratory abnormality, which, in the investigator's judgment, reasonably suspects that the patient has a medical condition or condition that is not suitable for the use of the investigational drug (such as having seizures and requiring treatment), or which would affect the interpretation of the study results or place the patient at high risk; 22. Urine routine indicated urinary protein ≥2+, and 24-hour urinary protein volume \>1.0g; 23. The patients considered by the investigators to be unsuitable for inclusion in this study.