• The age at randomization was at least 18 years old , and both men and women were eligible.

• histologically or cytologically confirmed inoperable locally advanced or metastatic gastric/esophagogastric junction adenocarcinoma who have failed at least two prior lines of therapy :

∙ Radiographic progression or clinical worsening of symptoms during second-line treatment (if first-line treatment includes three drugs including taxanes (or anthracyclines), platinums, and fluorouracils, and the disease progression is assessed by the investigator, the patient may also be enrolled as an eligible subject; disease progression within 6 months after the end of neoadjuvant/adjuvant treatment is also considered a first-line treatment failure);

‣ Patients with intolerance to second-line treatment may also be enrolled in the study after full evaluation by the investigator. The definition of intolerance to previous treatment is as follows:

• any Grade ≥ 3 (according to NCI CTCAE v5.0 criteria) hematologic toxicity that has not recovered to Grade 1 or pre-treatment levels after 14 days of best supportive care; any Grade ≥ 3 (according to NCI CTCAE v5.0 criteria) non-hematologic toxicity (excluding alopecia and asymptomatic laboratory abnormalities) that has not resolved after 14 days of best supportive care.

• Tumor tissue specimens (primary or metastatic, archived or newly collected) from subjects are expected to be available and tested by a central laboratory, indicating positive histological staining for CLDN18.2 (defined as a positive tumor cell rate ≥40% and a staining intensity ≥2+) . If the subject has previously received other CLDN18.2-targeted therapies, tumor tissue specimens collected after that treatment are required to retest and evaluate CLDN18.2 expression levels .

• The subject's expected survival period is ≥12 weeks.

• According to RECIST 1.1, there should be at least one stably measurable target lesion or evaluable lesion, and the longest diameter of the largest lesion (or the shortest diameter if it is a lymph node lesion) should be ≤5 cm .

• ECOG performance status score is 0-1.

• The subject must have adequate organ and bone marrow function. Laboratory screening must meet the following criteria. All laboratory test results should be within the stable ranges described below, and there should be no ongoing supportive treatment. If any laboratory test result is abnormal based on the following criteria , the test can be repeated within 1 week. If the test results still do not meet the following criteria , the patient has failed the screening.

∙ Blood tests \[no enhanced blood transfusion ( ≥ 2 times within 1 week), platelet transfusion, or cell growth factor (except recombinant erythropoietin) within 7 days before the examination\]: neutrophil count ≥ 1.5×10 9 /L; platelet count (PLT) ≥ 75×10 9 /L; hemoglobin content (Hb) ≥ 8.0 g/dL; lymphocyte (LYM) ≥ 0.5×10 9 /L;

‣ Liver function: alanine aminotransferase (ALT) ≤ 2.5×ULN, aspartate aminotransferase (AST) ≤ 2.5×ULN, serum total bilirubin (TB) ≤ 2×ULN; for patients with liver metastasis, AST and ALT \< 5×ULN;

‣ Renal function: Serum creatinine ≤ 1.5 × ULN. If serum creatinine is \> 1.5 × ULN, creatinine clearance \> 50 mL/min (based on the Cockcroft-Gault formula); qualitative urine protein ≤ 1+; if qualitative urine protein is ≥ 2+, a 24-hour urine protein quantitative test is required (a 24-hour urine protein quantitative test \< 1 g is acceptable);

‣ Amylase and lipase ≤ 1.5 × ULN; alkaline phosphatase (ALP) ≤ 2.5 × ULN. For patients with bone metastases, ALP \< 5 × ULN.

• All toxic reactions caused by previous anti-tumor therapy have been alleviated to Grade 0-1 (according to NCI CTCAE Version 5.0) or to a level acceptable to the inclusion/exclusion criteria. This excludes other toxicities such as alopecia and vitiligo that the investigator believes do not pose a safety risk to the subjects.

• Reproductive status: Female patients of childbearing age or male patients whose sexual partners are female patients of childbearing age are willing to take medically approved and highly effective contraceptive measures , such as intrauterine devices or condoms, from the time the informed consent is signed until 12 months after cell infusion (female patients of childbearing age include premenopausal women and women within 24 months of postmenopause).

⁃ The subjects must sign and date the written informed consent form.

⁃ Subjects must be willing and able to comply with the scheduled treatment regimen, laboratory tests, follow-up and other study requirements.