To evaluate the safety and efficacy of anti-CD56-CAR T in the treatment of relapsed refractory NK/T cell lymphoma /NK cell leukemia

Extranodal NK/TCL is an aggressive disease with a poor prognosis and a 5-year survival rate of less than 50%. In the absence of effective treatment, median survival for advanced disease is only 6-12 months. A retrospective review of the International Peripheral T-Cell Lymphoma Project recently reported that the median overall survival of NK/TCL was 7.8 months, corresponding to the worst survival of all T-cell lymphoma entities. Therefore, despite good results in the combination of chemoracal-chemotherapy strategies, autologous bone marrow transplantation, and L-asparagase in the treatment of recurrent cases, NK/TCL remains difficult to cure, and the need for alternative therapeutic strategies has prompted researchers to explore new molecular targets.

Nerve cell adhesion molecule 1 (NCAM-1) -CD56 is a member of the immunoglobulin superfamily and is a biomarker of nerve cell adhesion molecule and NK cell. CD56 is highly expressed in NK/T cell lymphomas, skeletal muscle tumors, and malignancies with neurological or neuroendocrine differentiation. CD56-CAR T cells can kill CD56+ neuroblastoma, glioma, and SCLC tumor cells in vitro coculture, and CD56R-CAR+T cells can inhibit tumor growth in vivo when tested against CD56+ human neuroblastoma xenogeneic and SCLC models. CD56-CAR T cells have also been reported as a safe and effective treatment for refractory/relapsing rhabdomyosarcoma. This indicates that CD56 CAR has a wide clinical application prospect and strong potential therapeutic value as a new CAR T target.

CD56 CAR T cells constructed by our laboratory can produce more precise killing effect on tumor cells by converting the immune checkpoint PD-1 signal. The results showed that CD56 CAR T cells could be prepared effectively and kill NK/ T-cell lymphoma cell line SNK-6 in vitro. Compared with traditional second-generation CAR T cells, CD56-CAR T cells prepared in our laboratory showed better killing effect on SNK-6 cells in vitro. At present, no clinical studies on CD56 CAR T therapy for NK/T cell lymphoma have been reported. Therefore, in this study, CD56 CAR T was used to treat relapsed and refractory NK/T cell lymphoma /NK cell leukemia to observe its safety and efficacy.

Inclusion Criteria:

1. Patients or their legal guardians voluntarily participate and sign the informed consent;
2. Male or female patients aged 18-70 years (including 18 and 70 years);
3. The patient was diagnosed as NK/T cell lymphoma /NK cell leukemia by pathology or flow cytometry, and currently has no effective treatment options, such as relapse after chemotherapy or hematopoietic stem cell transplantation; Alternatively, patients voluntarily choose to administer anti-CD56-CAR T cells as salvage therapy.
4. The following two categories are included:(1)NK/T cell lymphoma;(2) NK cell leukemia.
5. Subject:

(1)There was no remission or residual lesions after treatment, and HSCT (auto/allo-HSCT) was not suitable; (2)Relapse occurred after CR, and HSCT (auto/allo-HSCT) was not suitable; (3)Patients with high risk factors; (4)Relapse or no remission after hematopoietic stem cell transplantation or cellular immunotherapy.

6. Measurable or evaluable lesions;

7. The patient's main tissues and organs function well:

1. Liver function: ALT/AST < 3 times the upper limit of normal (ULN) and total bilirubin ≤34.2μmol/L;
2. Renal function: creatinine < 220 μmol/L;
3. Lung function: indoor oxygen saturation ≥95%;
4. Cardiac function: left ventricular ejection fraction (LVEF) ≥40%.

8. The patients had not received any anti-cancer treatment such as chemotherapy, radiotherapy, immunotherapy (such as immunosuppressive drugs) within the first 4 weeks of enrollment, and their previous treatment-related toxic reactions had recovered to ≤ grade 1 at the time of enrollment (except low toxicity such as hair loss);

9. The patient's peripheral shallow venous blood flow is smooth, which can meet the needs of intravenous infusion;

10. Patients with ECOG score ≤2 and expected survival time ≥3 months.

Exclusion Criteria:

1. Women who are pregnant (urine/blood pregnancy test positive) or breastfeeding;
2. Men or women who have planned to become pregnant within the last 1 year;
3. The patients were not guaranteed to take effective contraceptive measures (condoms or contraceptives, etc.) within 1 year after enrollment;
4. Patients had uncontrollable infectious diseases within 4 weeks prior to enrollment;
5. Active hepatitis B/C virus;
6. HIV-infected patients;
7. Suffering from a serious autoimmune disease or immunodeficiency disease;
8. The patient is allergic to antibodies, cytokines and other macromolecular biological drugs;
9. The patient had participated in other clinical trials within 6 weeks prior to enrollment;
10. Systemic use of hormones within 4 weeks prior to enrollment (except for inhaled hormones);
11. Suffers from mental illness;
12. The patient has substance abuse/addiction;
13. According to the researchers' judgment, the patient had other conditions that were not suitable for inclusion.