Allogeneic B7H3 CAR-γδT Cell Therapy for Advanced Solid Tumors

This study is an open-label, dose-escalation exploratory clinical trial using γδ T cells derived from healthy donors, genetically engineered to express a chimeric antigen receptor (CAR) targeting B7H3 on their membrane. Preclinical in vitro and in vivo experiments demonstrated the modified CAR-γδ T cells possess specific cytotoxicity against B7H3-positive tumor cells.

According to the patients' disease conditions, they were divided into an intravenous infusion group and an intraperitoneal infusion group. Both groups underwent a dose-escalation study using the "3+3" design.

Inclusion criteria

• Age ≥18 years old, gender is not limited;
• Expected survival time ≥3 months;
• ECOG score 0~1;
• Patients who meet the clinical diagnostic criteria and have a clear pathological diagnosis of malignant solid tumors that have failed standard treatment;
• Tumor tissue samples (specimens within one year are recommended) positive for B7H3 by immunohistochemical (IHC) staining or flow assay;
• Presence of at least one evaluable lesion according to RECIST V1.1;
• Tumors limited to peritoneal (metastatic) and ovarian cancer in patients in the laparotomy group;
• Substantially normal bone marrow reserve function and normal liver and renal function (laboratory tests need to be fulfilled before the first treatment with cell injection):

Blood: white blood cell count (WBC) ≥3E9/L, lymphocyte count (LY) ≥0.8E9/L, hemoglobin (Hb) ≥80g/L, platelet (PLT) ≥75E9/L; Liver: ALT ≤ 3 × ULN; AST ≤ 3 × ULN; total bilirubin ≤ 3.0 × ULN; Kidney: serum creatinine ≤ 1.5 × upper limit of normal range (ULN); Heart: left ventricular ejection fraction ≥50% on echocardiography; lung: normal oxygen saturation without oxygen.

• Pregnancy test should be negative for women of childbearing potential and both men and women agree to use effective contraception during treatment and for 1 year thereafter;
• Be able to understand the requirements and matters of the trial and be willing to participate in the clinical study as required;
• Sign the trial informed consent form.

Exclusion criteria

• Known hypersensitivity, allergy, intolerance, or contraindication to cell infusion or any of the drug components that may be used in the study, including fludarabine and cyclophosphamide;
• Patients who have been continuously using immunosuppressive drugs within 1 month prior to cell infusion;
• Cerebrovascular accident or seizure within 6 months prior to signing the informed consent form;
• Symptomatic brain metastases;
• a known psychiatric or substance abuse disorder that would interfere with cooperation with the trial requirements;
• Hepatitis B surface antigen (HBsAg) positivity or hepatitis B core antibody (HBcAb) positivity and a peripheral blood test for hepatitis B virus (HBV) DNA titer that is not within the normal reference range; hepatitis C virus (HCV) antibody positivity and peripheral blood hepatitis C virus (HCV) RNA positivity; human immunodeficiency virus (HIV) antibody positivity; syphilis Positive for syphilis;
• Serious cardiac disease: including, but not limited to, unstable angina pectoris, myocardial infarction (occurring within 6 months prior to screening), congestive heart failure (NYHA classification ≥ III), and severe arrhythmias;
• Presence of active or uncontrolled infections requiring systemic therapy (except for mild genitourinary and upper respiratory tract infections);
• has not recovered from acute toxic effects of prior therapy (prior therapy-induced hematologic or organ toxicity ≥ Grade 2, except for abnormalities related to study disease and medical history);
• have a confirmed diagnosis of an immunodeficiency
• suffering from an active infection requiring systemic therapy;
• a female subject of childbearing potential who plans to become pregnant within 2 years of cell infusion; or a male subject whose partner plans to become pregnant within 2 years of cell infusion;
• Participation in a clinical study of another innovative drug within 1 month prior to screening;