Autologous Transplantation Combined With BCMA CAR-T in the Treatment of Young NDMM

Inclusion Criteria: Young newly diagnosed multiple myeloma (NDMM), 18-50 years old, suitable for ASCT; 1. The subjects voluntarily participated in the study and signed the informed consent form (ICF) by themselves or their legal guardians; 2. The subject must have proper organ function and meet all the following inspection results: total serum bilirubin (TBIL) ≤ 1.5 times the upper limit of normal (ULN); serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5 × ULN; creatinine clearance (CrCl) (Cockcroft Gault formula) ≥ 40ml/min; prothrombin time (PT) ≤ 1.5 × ULN, partial prothrombin time (APTT) \< 1.5 × ULN; international normalized ratio (INR) \< 1.5 × ULN; hemoglobin (HB) ≥ 60g/L; absolute neutrophil count (ANC) ≥ 1.0 × 10\^9/lL(no growth factors such as granulocyte colony stimulating factor \[G-CSF\] have been received within 7 days before the laboratory examination in the screening period); absolute lymphocyte count (ALC) ≥ 0.5 × 10\^9/L; platelet (PLT) ≥ 50 × 10\^9/L (no platelet transfusion within 7 days before the laboratory examination in the screening period); left ventricular ejection fraction (LVEF) ≥ 45%; blood oxygen saturation (SpO2) ≥ 92%; 3. The ECOG score is 0-1. See Appendix V for ECOG score; 4. Estimated survival ≥ 3 months; 5. The pregnancy test of fertile female subjects should be negative and not during lactation. Exclusion Criteria: 1. Have a history of allergy to any component in cell products; 2. Serious heart disease, including but not limited to: myocardial infarction, cardiac angioplasty or stent implantation within 6 months before signing ICF; unstable angina; severe arrhythmia; history of severe non ischemic cardiomyopathy; congestive heart failure (New York Heart Association \[NYHA\] class III or IV), see Appendix II for NYHA score; 3. History of autologous / allogeneic hematopoietic stem cell transplantation; 4. Stroke or seizure within 6 months before signing ICF; 5. Have autoimmune diseases, immunodeficiency or other diseases that need immunosuppressant treatment; 6. Within 3 years before signing the ICF, patients with malignant tumors other than multiple myeloma, except for fully treated cervical carcinoma in situ, basal cell or squamous cell skin cancer, local prostate cancer after radical surgery, breast ductal carcinoma in situ after radical surgery, and carcinoma in situ in other parts one year after radical surgery, and there has been no treatment and no sign of recurrence in the screening period; 7. The presence of uncontrolled active infection; 8. Unstable systemic diseases judged by the investigator: including but not limited to serious liver, kidney or metabolic diseases requiring drug treatment; 9. One week before lymphocyte collection, the memory is under any of the following conditions: the detection value of hepatitis B virus (HBV) DNA in peripheral blood is higher than the lower limit of detection; hepatitis C virus (HCV) antibody positive and peripheral HCV-RNA positive.