A Clinical Study to Evaluate the Safety and Preliminary Efficacy of QI-019B in Patients With Relapsed/Refractory Multiple Myeloma.

Inclusion Criteria

• •1\. Age ≥ 18 years, any gender;
• •2\. Diagnosed with multiple myeloma (MM) according to IMWG diagnostic criteria;
• •3\. Have received at least 2 lines of anti-MM treatment, with at least one full treatment cycle per line, and experienced disease progression during the most recent anti-myeloma treatment or within 12 months after it, confirmed by available clinical evidence; or deemed by the investigator to be refractory to both immunomodulatory agents and proteasome inhibitors, with disease progression during the most recent anti-myeloma treatment or within 2 months after it (according to IMWG diagnostic criteria);
• •4\. Disease must be measurable at screening, meeting one or more of the following criteria:
• •* Serum M protein level ≥ 0.5 g/dL;
• •* Or urine M protein level ≥ 200 mg/24h;
• •* Or involved serum free light chain ≥ 10 mg/dL with abnormal serum free light chain κ/λ ratio;
• •5\. ECOG performance status 0-2, with an expected survival of ≥ 3 months;
• •6\. Bone marrow function test results (from screening or within 2 months prior) meet the following requirements:
• •* Hemoglobin ≥ 6 g/dL (no red blood cell transfusion within 1 week before screening), recombinant human erythropoietin allowed; for patients meeting the ≥ 6 g/dL hemoglobin requirement at screening, red blood cell transfusions are allowed to maintain hemoglobin ≥ 6 g/dL;
• •* Absolute neutrophil count (ANC) ≥ 600/μL (no use of granulocyte colony-stimulating factor (G-CSF) within 1 week before screening or pegylated G-CSF within 2 weeks before screening);
• •* Platelet count ≥ 50,000/μL;
• •* Lymphocyte count ≥ 500/μL;
• •7\. Normal renal function: Creatinine clearance (CrCl) (Cockcroft-Gault formula) ≥45 mL/min;
• •8\. Liver function must meet the following criteria:
• •* Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤3.0× the upper limit of normal (ULN);
• •* Total bilirubin (TBIL) and alkaline phosphatase (AKP or ALP) ≤2.0× ULN (except for congenital hyperbilirubinemia, e.g., Gilbert's syndrome, direct bilirubin ≤1.5× ULN);
• •* Albumin ≥3 g/dL;
• •9\. Cardiac function must meet the following criteria:
• •* Left ventricular ejection fraction ≥50% (by echocardiography or MUGA scan);
• •* No clinically significant pericardial effusion;
• •* No clinically significant electrocardiogram abnormalities;
• •10\. Pulmonary function must meet the following criteria:
• •• Blood oxygen saturation ≥90% without oxygen supplementation;
• •11\. Women of childbearing potential must have a negative pregnancy test at screening and before drug infusion and must not be breastfeeding.
• •12\. Men and women of childbearing potential must agree to use effective contraception from the time of signing the informed consent until 1 year after the use of the study drug;
• •13\. Men and women of childbearing potential must agree not to donate sperm or eggs (oocytes) or other reproductive cells from the time of signing the informed consent until 1 year after the use of the study drug;
• •14\. The subject or their legal guardian agrees to participate in this clinical trial and signs the informed consent form (ICF), indicating that they understand the purpose and procedures of this clinical trial and are willing to participate in the study.