A Study of BL-M11D1 in Patients With Relapsed/Refractory Acute Myeloid Leukemia

Prior treatment

• Antineoplastic therapy, including chemotherapy, biologic therapy, immunotherapy, definitive radiotherapy, major surgery (investigator-defined), or targeted therapy (including small-molecule tyrosine kinase inhibitors), has been administered within 4 weeks or 5 half-life cycles (whichever is shorter) before the first dose; Or palliative radiotherapy within 2 weeks before the first dose.
• Patients with pulmonary disease grade ≥3 defined by CTCAE v5.0, current or previous interstitial lung disease (ILD).
• Prior organ transplantation or allogeneic hematopoietic stem cell transplantation (Allo-HSCT).
• Had participated in another clinical trial within 4 weeks before the first dose (calculated from the time of last dose).

Other illness

• Active autoimmune diseases and inflammatory diseases, such as systemic lupus erythematosus, psoriasis requiring systemic treatment, rheumatoid arthritis, inflammatory intestinal diseases and Hashimoto's thyroiditis, etc., excluding type I diabetes mellitus, hypothyroidism that can only be controlled by replacement therapy, and skin diseases without systemic treatment (such as vitiligo and psoriasis).
• Other malignancies diagnosed within 5 years before the first dose, except for radical basal cell carcinoma, squamous cell carcinoma, and/or radical resection carcinoma in situ.
• Poorly controlled hypertension (systolic blood pressure \> 150 mmHg or diastolic blood pressure \> 100 mmHg).
• Patients with a history of allergy to recombinant humanized antibody or human-mouse chimeric antibody or to any of the ingredients of BL-M11D1.
• Human immunodeficiency virus (HIVAb) positive, active tuberculosis, active hepatitis B virus infection (HBsAg positive; HBcAb positive and HBV-DNA copy number \> lower detection limit) or active hepatitis C virus infection (HCV antibody positive and HCV-RNA \> lower detection limit).
• Active infection requiring systemic treatment, such as severe pneumonia, bacteremia, sepsis, etc.
• Other conditions for participation in the trial were not considered appropriate by the investigator.

Lab values

• History of severe heart disease, such as left ventricular ejection fraction \< 50%, history of symptomatic congestive heart failure (CHF) ≥ grade 2 (CTCAE v5.0), New York Heart Association (NYHA) ≥ grade 2 heart failure, history of myocardial infarction, unstable angina, etc.
• Prolonged QT interval (QTc \> 450 msec in men or QTc \> 470 msec in women), complete left bundle branch block, and III degree atrioventricular block.

Other

• Acute promyelocytic leukemia, acute transformation of chronic myeloid leukemia.
• Patients with central nervous system involvement.
• Presence of pleural, abdominal, pelvic or pericardial effusion with clinical symptoms or requiring repeated drainage.
• Pregnant or lactating women.

• Voluntarily sign the informed consent form and comply with the protocol requirements;
• No gender restrictions;
• Age: ≥18 years and ≤75 years;
• Expected survival time ≥3 months;
• Histologically and/or cytologically confirmed CD33-positive relapsed/refractory acute myeloid leukemia (AML);
• Morphological assessment showing ≥5% blasts in the bone marrow;
• ECOG performance status score ≤2;
• Peripheral blood white blood cell count ≤25×10\^9/L before the first dose;
• Toxicity from prior anti-tumor therapy has recovered to ≤ Grade 1 as defined by NCI-CTCAE v5.0;
• Organ function levels meet the requirements within 7 days before the first dose;
• For premenopausal women with childbearing potential, a pregnancy test (serum/urine) must be performed within 7 days before starting treatment, and the result must be negative; they must not be breastfeeding. All enrolled patients (regardless of gender) must use adequate barrier contraception throughout the treatment period and for 6 months after treatment ends.