A Clinical Study on the Safety and Efficacy of CAR-T Therapy for the TM4SF1-positive Tumors of Digestive System

Transmembrane 4 L Six Family Member 1 (TM4SF1) is highly expressed in many tumors of digestive system .

The Chimeric Antigen Receptor T-cells (CAR-T) that target TM4SF1 has been generated in our good manufacturing practices (GMP) facility and the anti-tumor effects have been demonstrated in multiple in vitro and in vivo studies.

Clinical studies are proposed here to evaluate the anti-tumor activity of these cell therapy products for treatment of patients with TM4SF1 positive tumors of digestive system. In this study, the safety, tolerance, and preliminary efficacy of CART-TM4SF1 cells will be examined in patients with refractory/recurrent advanced pancreatic cancer, colorectal cancer, gastric cancer or liver cancer.

Clinical and immunological responses will be evaluated about 30 days and last up to 2 years after CAR-T cell infusion.

Background:

While great progress has been made in CAR T-cell therapy for the treatment of hematologic malignancies, its use in solid tumors is still at the exploratory stage.Transmembrane 4 L Six Family Member 1 (TM4SF1) protein mediates signal transduction events that play a role in the regulation of cell development, activation, growth and motility. It is a cell surface antigen and is highly expressed in different carcinomas.The investigators have developed novel TM4SF1-targeting CAR T-cells (CART-TM4SF1 cells) for the treatment of digestive system tumors.

These engineered T-cells can target and kill the TM4SF1-positive tumor cells in vitro or in mice. Both of the CAR molecules contain a safety switch based on epidermal growth factor receptor (EGFR) to ensure the safety.The investigators propose to investigate the feasibility, safety, and efficacy of CART-TM4SF1 cells for digestive system tumors in patients.

Objectives:

Primary objectives:

1. To determine the safety/tolerance dosages and adverse effects of CART-TM4SF1 cells cells in the treatment of TM4SF1-positive recurrent/refractory advanced tumors of digestive system.
2. To preliminarily evaluate the efficacy of CART-TM4SF1 cells in the treatment of TM4SF1-positive recurrent/refractory advanced tumors of digestive system.

Secondary objectives:

1. To determine the pharmacokinetic (PK)/pharmacodynamic (PD) characteristics of CART-TM4SF1 cells in humans.
2. To evaluate the overall survival (OS) and tumor regression after treatment.
3. To assess the life quality of patients

Study population:

The study population includes 12-24 patients with refractory/recurrent advanced digestive system tumors with positive expression of TM4SF1. The subjects will receive four incremental doses (3-6 subjects in each dose group), as well as safety and preliminary efficacy evaluation.

Design:

* This is a single-center open-label clinical study.
* Recruit patients with refractory/recurrent digestive system tumors, with written consent for this study. Perform biopsy to determine the expression of TM4SF1 of the tumor with immuno-histochemistry (IHC).
* Collect peripheral blood mononuclear cell (PBMC) from the patients, isolate and activate the T cells and transfect them with TM4SF1 targeting CAR, expand the transfected T cells as needed, assess the quality and antitumor activity of the CAR-T products in vitro and then transfer them back the patients via systemic or local injections, and follow up closely to collect related results as needed.
* Clinical and immunological responses will be evaluated closely in about 30 days and last up to 2 years after back-transfusion.

Eligibility Criteria:
Inclusion Criteria:

1. The age at the time of signing the informed consent is ≥ 18 years old and ≤ 75 years old, regardless of gender;
2. BMI ≥ 18.5 (weight (kg)/height (m ²）)；
3. The physical condition score of the Eastern Cooperative Oncology Group (ECOG) is ≤ 2 points;
4. The estimated survival time is not less than 12 weeks;
5. Patients confirmed by histology or cytology, who progress after standard treatment failure, or cannot accept/fail patients with advanced solid tumors with standard treatment, such as gastric cancer, colorectal cancer, pancreatic cancer and other digestive system tumors.
6. According to RECIST 1.1 standard, there is at least one measurable lesion, that is, according to CT or MRI cross section on imaging, the long diameter of non lymph node lesions ≥ 10 mm, or the short diameter of lymph node lesions ≥ 15 mm; measurable disease CT scanning of the longest axis of the focus ≥ 10 mm (CT scanning slice thickness ≤ 5 mm), and the measurable part should not be accepted local treatment such as radiotherapy (for lesions located in the previous radiotherapy area, if progress is confirmed, it is also optional target lesion);
7. It has suitable organs and hematopoietic function (It is not allowed to use any blood components, cytokines, leukemic agents, platelet promoting agents and human albumin preparations within 14 days before screening), according to the following laboratory tests:

   1. Color Doppler echocardiography showed normal diastolic function, left ventricular ejection fraction (LVEF) ≥ 50%, and no large amount of pericardial effusion
   2. Finger oxygen saturation\>93%；
   3. Neutrophil (ANC) ≥ 1.5 × 10 9 /L；
   4. Platelet count≥75×10 9 /L；
   5. Hemoglobin (HGB)\>90g/L；
   6. Absolute lymphocyte count (ALC)≥0.8×10 9 /L；
   7. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 times the upper limit of normal value (ULN) in patients without liver metastasis and ≤ 3.5 times ULN in patients with liver metastasis;
   8. total bilirubin≤1.5 times ULN；
   9. Creatinine ≤ 1.5 times ULN;
   10. Prothrombin time (PT) or international normalized ratio(INR)\<1.5 times ULN, and partial thromboplastin time (APTT)\<1.5 times ULN.
8. The expression of TM4SF1 is positive, which can be divided into two cases, and it can meet one of the following conditions：

   1. The tumor tissue samples with recurrence at the primary site or presence of the primary site and within 1 year were detected as high expression of TM4SF1 by immunohistochemistry;
   2. The high expression of TM4SF1 was detected by immunohistochemistry after biopsy in non primary tumor metastasis;
9. Women of childbearing age must have negative pregnancy results during screening period and before drenching treatment.
10. The subject voluntarily joined the group and signed the informed consent form, and voluntarily followed the trial treatment scheme and visit plan.

Exclusion Criteria:

1. Subjects with allergic constitution and allergy to immunotherapy or related drugs；
2. Adverse reactions of previous treatment failed to recover to CTCAE v5.0 grade ≤ 1 ；
3. Patients expected to have major surgery during the study period, including the screening period;；
4. Patients with severe autoimmune diseases requiring long-term (more than 2 months) systemic immunosuppressive therapy;；
5. Any unstable systemic disease: including but not limited to unstable angina pectoris, cerebrovascular accident, transient cerebral ischemia (within 6 months before screening), myocardial infarction (within 6 months before screening), congestive heart failure（≥ NYHA Class III）, severe arrhythmia with poor drug control, liver, kidney or metabolic disease, and hypertension beyond control through standard treatment
6. Known or suspected brain metastasis, including central nervous system and spinal cord compression or meningeal metastasis patient；
7. Other active malignant tumors in the past 5 years
8. Patients with active bleeding and thrombotic disease requiring treatment;
9. Patients with pleural and peritoneal effusion who cannot be controlled and need clinical treatment or intervention；
10. Patients who used corticosteroid hormones (prednisone ≥ 20mg/day or other corticosteroid hormones with equivalent dose) and other immunosuppressants with pharmacological dose 7 days before cell collection and 5 days before cell reinfusion in this study；
11. Alcohol dependent persons or those who have a history of drug abuse or drug abuse in the past one year；
12. Subjects with any mental illness that may affect the understanding of informed consent；
13. Patients with acute or chronic active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection; Patients with human immunodeficiency virus (HIV) antibody positive; Patients with treponema pallidum antibody test positive