The goal of this study is to observe and evaluate the incidence of infection in newly diagnosed, non-transplanted multiple myeloma patients receiving prophylactic treatment with sulpegfilgrastim (a pegylated recombinant human granulocyte colony-stimulating factor).

It is a study on the use of sulpegfilgrastim to prevent the incidence of neutropenia with infection in newly diagnosed non-transplant multiple myeloma patients. Patients enrolled in this study may be treated with the following oncological protocols:DRD regimen (CD38 monoclonal antibody + lenalidomide + dexamethasone).On Day 1 of each oncological treatment cycle, after administration of the CD38 monoclonal antibody, a subcutaneous injection of Sulfubrolipoyl G-CSF will be given. The recommended fixed dose of Sulfubrolipoyl G-CSF is 6 mg per injection. The study will observe six treatment cycles. After the study concludes, the next treatment steps will be jointly decided by the investigator and the patient. If a patient's neutrophil level remains below 0.5×10⁹/L for over 24 hours after receiving Sulfubrolipoyl G-CSF, the investigator will assess the need for rescue treatment with short-acting G-CSF based on the patient's condition until the neutrophil level returns to normal.Prophylactic antibiotic treatment may be administered before the onset of oncological treatment. The goal is to observe and evaluate the incidence of infection in newly diagnosed, non-transplanted multiple myeloma patients receiving prophylactic treatment with sulpegfilgrastim (a pegylated recombinant human granulocyte colony-stimulating factor).

Inclusion Criteria:

Patients must meet all the following criteria to be eligible for this study:

1. Age ≥ 18 years old，weight > 35 kg，regardless of gender;
2. Voluntarily participating in the study after signing the informed consent form;
3. Newly diagnosed, non-transplanted multiple myeloma patients diagnosed according to the 2016 International Myeloma Working Group (IMWG) criteria or the 2024 Chinese Guidelines for the Diagnosis and Treatment of Multiple Myeloma, and expected to receive at least six cycles of DRD (CD38 monoclonal antibody + lenalidomide + dexamethasone) oncological treatment;
4. Deemed suitable for sulpegfilgrastim administration by the investigator;
5. Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) score of 0-2, with an expected survival of at least three months;
6. Absolute neutrophil count (ANC) ≥ 1.5×10⁹/L; platelet count (PLT) ≥ 75.0×10⁹/L；
7. Serum creatinine clearance rate ≥30 mL/min; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels ≤three times the upper limit of normal。
8. Negative pregnancy test for women of childbearing age. Patients and their spouses must agree to use effective contraceptive measures during treatment and for one year thereafter；
9. Signed informed consent for chemotherapy. In cases where the patient is unable to sign due to impaired consciousness, upper limb paralysis, or illiteracy, a legal representative may sign on their behalf.

Exclusion Criteria:

Patients meeting any of the following criteria are excluded from this study：

1. Weight≤35kg；
2. Monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma, or primary light chain amyloidosis with organ involvement;
3. Diagnosed or treated for another malignancy within one year prior to registration, or evidence of residual disease from a previous malignancy requiring ongoing treatment;
4. Known positive for human immunodeficiency virus (HIV);
5. Pregnant or breastfeeding women;
6. Patients with any active acute infection, including viral infections;
7. Patients who have received systemic antibiotic treatment within two weeks prior to enrollment;
8. Allergy to Sulfubrolipoyl G-CSF, pegylated recombinant human granulocyte colony-stimulating factor, recombinant human granulocyte colony-stimulating factor, or other agents expressed in E. coli; Other situations where the investigator deems participation in the study inappropriate.

To observe and evaluate the incidence of infection in newly diagnosed, non-transplanted multiple myeloma patients receiving prophylactic treatment with sulpegfilgrastim (a pegylated recombinant human granulocyte colony-stimulating factor).