Study of The Second-line Treatment of Advanced Gastric / Gastroesophageal Junction Adenocarcinoma With Cadonilimab and Fruquintinib Combined With Paclitaxel-albumin

Inclusion Criteria: Signed written informed consent prior to enrollment. Age 18-80 years. Negative for HER2Diagnosis confirmed by histological examination and/or cytological examination combinedwith imaging assessment of advanced metastatic gastric/gastroesophageal junctionadenocarcinoma. Failure of previous first-line therapy. Group A (immunotherapy naive ): patients who havefailed prior chemotherapy with first-line standard therapy. Group B (immunotherapyrechallenge): patients who had previously failed PD-1/L1 antibody combined chemotherapy inthe first line. ECOG score: 0 to 1. At least one measurable lesion (≥10 mm long diameter on CT scan fornon-lymph node lesions and ≥15 mm short diameter on CT scan for lymph node lesionsaccording to iRECIST criteria). Adequate organ function with. Routine blood: Absolute Neutrophil Count (ANC) 1.5 × 109/L,Platelets (Platelet, PLT) ≥ 100 × 109/L, Hemoglobin (HGB) ≥ 90 g/L. Liver function: Total Bilirubin (TBIL) ≤ 1.5 × Upper Limit of Normal Value (ULN); AlanineAminotransferase (ALT) and Aspartate Transferase (AST) ≤3×ULN; serum albumin ≥30 g/L; afterconventional hepatoprotective treatment meeting the above criteria, and can be stable forat least 1 week after evaluation by the investigator can be enrolled. Renal function: Creatinine (Cr) ≤ 1.5 × ULN, or creatinine clearance ≥ 50 mL/mi (applyingthe standard Cockcroft-Gault formula). Coagulation function: International Normalized Ratio (INR) ≤ 1.5 /PT ≤ 1.5 × ULN, aPTT ≤ 1.5 × ULN; if the subject is receiving anticoagulation therapy, as long as PT and INR arewithin the range drawn up by anticoagulant drugs. A predicted survival of ≥ 3 months. Female patients must be non-pregnant and non-lactatingand are required to use a medically approved form of contraception (e.g., IUD, pill orcondom) during study treatment and for at least 120 days after study completion, and arenot allowed to donate eggs to another person or freeze them for fertilization andpropagation during this period.

Exclusion Criteria: Symptomatic brain metastases. Known MSI-H/dMMR. A prior history of a primary tumor outsideof the gastric/gastroesophageal junction in 3 years Active autoimmune disease or autoimmunedisease with potential for recurrence such as, but not limited to: autoimmune hepatitis,interstitial pneumonia, uveitis, enterocolitis, hepatitis, pituitary inflammation,vasculitis, nephritis, hyperthyroidism, hypothyroidism, previous thyroid surgery cannot beincluded; subjects with vitiligo or complete remission of asthma in childhood and adult whodo not require any intervention afterwards can be included; subjects with asthma requiringmedical intervention with bronchodilators cannot be included. Subjects with any severe and/or uncontrolled disease. including. Poorly controlled bloodpressure (systolic blood pressure ≥ 150 mmHg or diastolic blood pressure ≥ 100 mmHg);poorly controlled diabetes (fasting blood glucose [FBG] > 10 mmol/L) Having ≥ grade 2myocardial ischemia or myocardial infarction, arrhythmia (QTc ≥ 470ms) and ≥ grade 2congestive heart failure (New York Heart Association [NYHA] classification) Active oruncontrolled severe infection (≥ CTCAE grade 2 infection) requiring systemic antibacterial,antifungal or antiviral therapy, including tuberculosis infection Active hepatitis (transaminases do not meet the inclusion criteria, hepatitis B reference: HBV DNA ≥ 1000IU/ml or ≥ 10^4 copies/ml; hepatitis C reference: HCV RNA ≥ 1000 IU/ml or ≥ 10^4 copies/ml;after nucleotide based antiviral therapy below the above criteria, can be enrolled);chronic hepatitis B virus carriers with HBV DNA < 10^4 IU/ml, who must receive concomitantantiviral therapy during the trial to be enrolled. Those with renal failure requiring hemodialysis or peritoneal dialysis. Those with ahistory of immunodeficiency, including HIV-positive or suffering from other acquired orcongenital immunodeficiency diseases, or a history of organ transplantation Activeautoimmune disease requiring systemic therapy (e.g., use of disease-relieving drugs,corticosteroids, or immunosuppressive agents) within 2 years prior to the start of studytreatment, except for replacement therapies (e.g., thyroxine, insulin, or physiologiccorticosteroids for adrenal or pituitary insufficiency); receiving systemic glucocorticoidtherapy or any other form of immunosuppressive therapy. Doses >10 mg/day of prednisone orother equivalent hormone and within 2 weeks of the first dose and still continuing Thosewith a history of active tuberculosis Those who fail to control and still require repeateddrainage of ascites, pericardial effusion, pleural effusion. Research treatment related to. Patients who have undergone major organ transplantationThose who have undergone major surgical treatment, incisional biopsy or significanttraumatic injury within 28 days prior to the start of study treatment; or have along-standing untreated wound or fracture History of live attenuated vaccination within 14days prior to the start of study treatment or planned live attenuated vaccination duringthe study History of severe hypersensitivity reactions following the use of monoclonalantibodies; known hypersensitivity to active ingredients or excipients such as envafolimab,lenvatinib, etc., of this study drug Those who are participating or have participated inother clinical studies within 4 weeks prior to the start of the study Those who havereceived taxanes, anti-angiogenic agents, and dual immunotherapy during first-linetreatment. Those with a history of severe allergy. Women who are pregnant or breastfeeding At risk forbleeding, or with coagulation disorders, or undergoing thrombolytic therapy Those with ahistory of psychotropic substance abuse and unable to abstain or with psychiatric disordersSubjects who, in the judgment of the investigator, have a concomitant disease thatseriously jeopardizes the safety of the subject or interferes with the completion of thestudy, or subjects for whom other reasons are deemed to exist that make them unsuitable forenrollment In the judgment of the investigator, subjects who, in the judgment of theinvestigator, have a concomitant disease that seriously jeopardizes the safety of thesubject or interferes with the completion of the study, or subjects for whom other reasonsare deemed to exist that make them unsuitable for enrollment.