Bezpečnost a účinnost NK520 k léčbě recidivující/refrakterní akutní myeloidní leukémie

Inclusion Criteria:

1. Participants must be between 18 and 75 years;

2. Diagnostic Criteria:

   Meet the 2016 World Health Organization (WHO) diagnostic criteria for acute myelocytic leukemia (AML), unsuitable for current treatments or patients with relapsed/refractory AML after ≥2 lines of therapy. The definition of relapsed/refractory acute myeloid leukemia is based on the 2017 Chinese Guidelines for Diagnosis and Treatment:

   1. Relapsed AML: Diagnosis is confirmed when leukemia cells reappear in the peripheral blood or bone marrow blast cells exceed 5% after complete remission (CR) (excluding reasons such as bone marrow regeneration post-consolidation chemotherapy) or there is extramedullary infiltration by leukemia cells;
   2. Refractory AML: Initial cases unresponsive after two cycles of standard regimen treatment; recurrence within 12 months after CR and consolidation therapy; recurrence beyond 12 months with ineffectiveness of conventional chemotherapy; those who have relapsed twice or more; or persistent extramedullary leukemia;

3. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2;

4. Expected survival of at least 12 weeks;

5. Normal Organ Function.

Exclusion Criteria:

1. Acute promyelocytic leukemia;

2. Severe bleeding tendency or coagulation disorders, or currently receiving thrombolytic therapy;

3. Active tuberculosis (TB), currently undergoing anti-TB treatment, or treated for TB within 1 year prior to the study;

4. Human immunodeficiency virus (HIV)-infected individuals, or known active syphilis infection;

5. Use of immunosuppressive drugs within 1 week before the first dose, excluding topical, inhaled, or other locally administered glucocorticoids, or physiologic doses of systemic glucocorticoids (not exceeding 10 mg/day prednisone equivalent) for allergic reactions or for managing respiratory distress from asthma, chronic obstructive pulmonary disease (COPD), etc;

6. Receipt of live attenuated vaccines within 2 weeks before the first dose or planned during the study;

7. Participation in another clinical trial and receipt of investigational drug within 4 weeks prior to the first dose;

8. Receipt of immune-modulating drugs (including thymosin, interferons, except for local use to control pleural or ascitic fluid) within 2 weeks prior to the first dose;

9. At screening, hepatitis B or C viral tests positive according to either:

   • Hepatitis B surface antigen (HBsAg) positive with serum hepatitis B virus- deoxyribonucleic acid (HBV-DNA) titer ≥1×10^3 copies/mL or above normal limits;
   • Hepatitis C virus (HCV) antibody positive;

10. Any other condition or situation in which the investigator deems the patient unsuitable for participation in this study.