This study is an exploratory single-arm, open, modified "3+3" dose escalation study with BGT007H injection. Approximately 11 to 14 subjects with recurrent/refractory gastrointestinal tumors will be enrolled to evaluate the safety of BGT007H injection.

Four dose levels were designed for this study: 1.0×10^8cells, 3.0×10^8cells, 1.0×10^9cells, and 3.0×10^9cells. The primary objective of this study was to evaluate the safety, tolerability and pharmacokinetic profile of BGT007H cell therapy in patients with recurrent/refractory digestive tract tumors, to determine the maximum tolerated dose or the best effective dose, and to initially evaluate the effectiveness of BGT007H cell products.

Main research objectives:

Evaluation of the safety and tolerability of BGT007H cell therapy in patients with recurrent/refractory gastrointestinal tumors

Secondary research objectives:

1. Evaluate the pharmacokinetic (PK) characteristics of BGT007H cells after reinfusion;
2. Evaluation of the initial effectiveness of BGT007H cell therapy in patients with recurrent/refractory gastrointestinal tumors

Exploratory Purpose

1. Exploring the correlation between the proliferation and survival of BGT007H cells in vivo and their therapeutic effects;
2. Exploring the correlation between target expression levels and efficacy

Inclusion Criteria:

• 1. Resources sign written informed consent;
• 2, age ≥18, male and female can;
• 3. Expected survival ≥3 months;
• 4. The Eastern Cancer Collaboration (ECOG) physical status score was 0-1;
• 5. Biopsy specimen or pathological wax section test (within 3 years before accepting the signed informed consent) : positive target test;
• 6. According to RECISTv1.1 solid tumor evaluation criteria, there is at least one measurable lesion;
• 7. Patients with advanced gastrointestinal tumors (esophageal cancer, gastric cancer, pancreatic cancer or colorectal cancer, etc.) who have been diagnosed by histology/cytology as having failed the standard of second-line or above treatment or are not suitable for/refuse to accept the standard treatment or cannot tolerate the standard treatment; The definition of intolerance: according to CTCAE V5.0, the occurrence of ≥Ⅳ hematological toxicity or ≥Ⅲ non-hematological toxicity or ≥Ⅱ damage to the heart, liver, kidney and other important organs during treatment; Treatment failure is defined as disease progression (PD) during treatment or recurrence after the end of treatment (including postoperative recurrence);
• 8, can establish monopexy or venous blood collection venous access, and there are no other contraindications for blood cell separation;
• 9, with adequate organ and bone marrow function;
• 10. During the study period and for 6 months after the end of dosing, fertile subjects (both male and female) must use effective medical contraception. For female subjects of reproductive age, a pregnancy test should be performed within 72 hours before the first dose, and the result is negative.

Exclusion Criteria:

• 1. Active central nervous system metastasis (except stable after treatment);
• 2, HIV positive, HBsAg positive simultaneously detected HBV DNA copy number positive (quantitative detection ≥1000cps/ml), HCV antibody positive and HCV RNA positive;
• 3, mental or mental illness can not cooperate with treatment and efficacy evaluation;
• 4. Subjects with severe autoimmune diseases and long-term use of immunosuppressants;
• 5. Active or uncontrollable infection requiring systemic treatment within 14 days prior to enrollment;
• 6. Any unstable systemic disease (including but not limited to: Active infections (except local infections); Unstable angina pectoris Cerebral ischemia or cerebrovascular accident (within 6 months prior to screening) Myocardial infarction (within 6 months prior to screening) Congestive heart failure (New York Heart Association [NYHA] classification ≥Ⅲ; Severe arrhythmias requiring medical treatment; Have heart disease that requires treatment or uncontrolled hypertension after treatment (blood pressure > 160mmHg/100mmHg);
• 7, combined with lung, brain, kidney and other important organ dysfunction;
• 8. The subject has undergone major surgery or severe trauma within 4 weeks prior to receiving cell therapy, or is expected to undergo major surgery during the study period;
• 9. Received any systemic chemotherapy, immunotherapy or small molecule targeted therapy within 1-2 weeks or 5 half-lives (whichever is shorter) before anapheresis;
• 10. The subject currently has or has had other malignant tumors that cannot be cured within 3 years, except cervical cancer or basal cell carcinoma of the skin, and other malignant tumors with a disease-free survival of more than 5 years;
• 11, received chimeric antigen receptor modified T cells (including CAR-T, CTT-T) treatment within half a year;
• 12. Combined graft-versus-host disease (GVHD)
• 13. Subjects who were receiving systemic steroid therapy prior to screening and who were determined by the investigator to require long-term use of systemic steroid therapy during treatment (except for inhalation or topical use); And subjects treated with systemic steroids within 72 hours prior to cell transfusion (except for inhalation or topical use);
• 14. Severe allergy or history of allergy;
• 15. Subjects requiring anticoagulation therapy;
• 16, pregnant or breastfeeding women, or six months within the pregnancy plan (unisex;
• 17. Researchers believe that there are other reasons for not being included in the treatment.