CD73/AXL Targeted HypoSti.CAR-T Cells in CD73/AXL Positive Advanced/Metastatic Solid Tumors

Phase I/II Clinical Trial of CD73/AXL Targeted HypoSti.CAR-T Cells in Treating Patients With CD73/AXL Positive Advanced/Metastatic Solid Tumors

In this single-center, single-arm,prospective, open-label, phase 1/2 study, the safety and efficacy of novel autologous hypoxia-activated CAR-T cell therapy targeting CD73 and AXL ( CD73/AXL.HypoSti.CAR-T) will be evaluated in patients with CD73/AXL antigen positive advanced/metastatic solid tumors. In this clinical trial, at least 12 eligible patients in dose escalation period will be enrolled to receive 3 doses Of CD73/AXL.HypoSti.CAR-T cell therapy according to the "3+3" principle. In dose expansion period, additional at most 21 eligible patients will be enrolled to receive CD73/AXL.HypoSti.CAR-T cell therapy at dose of recommended phase 2 dose(RP2D).

Currently, CAR T-cell therapy still faces significant challenges in its application to solid tumors due to multiple obstacles, including the lack of tumor-specific antigens, the complex immunosuppressive tumor microenvironment (TME), tumor heterogeneity, and on targeted/non-targeted (OTOT) toxicity. Previous studies have found that intratumoral hypoxic microenvironment facilitated the development and metastasis of tumor cells. Meanwhile, cytotoxic T cells, including CAR-T cells, struggle to survive and proliferate in this low-oxygen microenvironment.

CD73 (also known as 5'-nucleotidase) and AXL (a receptor tyrosine kinase) are both overexpressed in multiple solid tumors, but less so in normal tissues. They are both involved in regulating tumorigenesis, development, metastasis processes, correlating with inferior prognosis.Dual targeting of CD73 and AXL can effectively address antigen escape and tumor heterogeneity, representing a promising novel immunotherapy strategy.

In this study, combining hypoxia-activated precision with dual-targeting synergy,Investigators have developed a novel CD73/AXL.HypoSti.CAR-T that could effectively expand and survive in hypoxic TME ,offering enhanced efficacy and safety for solid tumors in animal models. Further clinical development is warranted to validate these promising preclinical results. So we conduct this clinical trial in order to test the the safety profiles and anti-tumor activities of CD73/AXL.HypoSti.CAR-T cell in vivo. In dose escalation period, at least 12 eligible patients will be enrolled and receive 3 doses of CD73/AXL.HypoSti.CAR-T cell therapy (1 × 10^6 cells/ kg, 3 × 10^6 cells/kg, 1 × 10^7 cells/kg) according to the "3+3" principle. In dose expansion period, additional at most 21 eligible patients will be enrolled to receive CD73/AXL.HypoSti.CAR-T cell infusion at RP2D, which is determined by data from dose escalation period, including occurrence of dose limiting toxicities (DLT), pharmacokinetics/pharmacodynamics, efficacy and other parameters, to furtherly evaluate the safety and efficacy profiles of CD73/AXL.HypoSti.CAR-T cell therapy.

Inclusion Criteria:

1. Age 18-75 (inclusive).

2. The Eastern Cooperative Oncology Group (ECOG) score ≤2 and Estimated life expectancy of more than 3 months.

3. Histopathological confirmed advanced or metastatic solid tumors failed to at least first-line treatment or initially diagnosed advanced/metastatic solid tumors that have no National Comprehensive Cancer Network (NCCN) guideline recommended standard firstline therapy. Tumor types include but are not limited to:biliary malignancies, pancreatic cancer, lung cancer, breast cancer, head and neck malignancies, gynecological tumors, etc.

4. The expression of CD73 or AXL antigen is≥50%.

5. At least one measurable lesion at baseline per RECIST version 1.1.

6. Fresh solid tumor samples or formalin-fixed paraffin embedded tumor archival samples within 6 months are necessary; Fresh tumor samples are preferred. Subjects are willing to accept tumor rebiopsy in the process of this study.

7. Adequate organ function as defined by the following criteria:

   • Absolute neutrophil count (ANC) ≥ 1 x 10^9/L, Platelet count ≥75 x 10^9/ L, hemoglobin (Hgb) ≥ 90g/L ;
   • Serum creatinine≤1.5 upper limit of normal (ULN) or creatinine clearance (as estimated by Cockcroft Gault) ≥60 mL/min;
   • Serum aspartate amino transferase (AST) and alanine aminotransferase (ALT), ≤3.0 x ULN (≤5 x ULN for patients with liver cancer or metastases); Total serum bilirubin ≤1.5 x ULN(≤3 x ULN for patients with liver cancer or metastases);
   • Cardiac ejection fraction ≥ 50%, no evidence of pericardial effusion as determined by an echocardiogram (ECHO), and no clinically significant electrocardiogram (ECG) findings;
   • International Normalized Ratio (INR) ≤ 1.5 times the upper limit of normal (ULN), and Activated Partial Thromboplastin Time (APTT) ≤ 1.5 times ULN;
   • Baseline oxygen saturation >91% on room air.

8. Previous treatment must be completed for more than 4 weeks prior to the enrollment of this study, and subjects have recovered to <= grade 1 toxicity (except for hematological toxicities and clinically non-significant toxicities such as alopecia).

9. Pregnancy tests for women of childbearing age shall be negative; Both men and women agreed to use effective contraception during treatment and during the subsequent 1 year.

10. Ability to understand and sign a written informed consent document.

Exclusion Criteria:

1. Subjects are being treated with either corticosteroids (>10 mg daily prednisone equivalent) or other immunosuppressive medications within 14 days of enrollment.
2. Received cytotoxic chemicals, monoclonal antibodies, immunotherapy, targeted therapy or other anti-tumor therapy within 4 weeks or 5 half-lives before enrollment.
3. Pregnant, lactating, or breastfeeding females.
4. Known positive test result for human immunodeficiency virus (HIV) or acquired immune deficiency syndrome (AIDS);Active infection of hepatitis B virus (HBV), or hepatitis C virus (HCV).
5. History of allergy or intolerance to study drug components.
6. Prior organ allograft transplantations or allogeneic hematopoietic stem cell transplantation.
7. Major surgery or trauma occurred within 28 days prior to enrollment, or major side effects have not been recovered.
8. Known brain metastases or active central nervous system (CNS).Subjects with CNS metastases who were treated with radiotherapy for at least 3 months prior to enrollment, have no central nervous symptoms and are off corticosteroids, are eligible for enrollment, but require a brain MRI screening.
9. Previous or concurrent cancer within 5 years prior to treatment start except for curatively treated cervical cancer in situ, non-melanoma skin cancer, superficial bladder tumors.
10. Uncontrolled intercurrent illness, including ongoing or active systemic infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia (excluding insignificant sinus bradycardia and sinus tachycardia) or psychiatric illness/social situations and any other illness that would limit compliance with study requirements and jeopardize the safety of the patient.
11. Active bleeding or known hemorrhagic tendency.
12. Vaccination within 30 days of study enrollment.
13. Being participating any other trials or withdraw within 4 weeks.
14. Researchers believe that other reasons are not suitable for clinical trials.