Patients will receive 3-4 cycles induction treatment, and high-dose melphalan conditioning, followed by autologous transplantation.Three months post-transplant, patients will undergo 2-3 cycles of consolidation therapy, followed by maintenance therapy for ≥2 years or until disease progression, death, intolerance, withdrawal for other reasons, or the study's termination/completion.

Patients will receives 3-4 cycles of induction therapy, 2-3 cycles of consolidation treatment, followed by Fc-based conditioning and CAR-T cell infusion. One month after CAR-T cell therapy, patients will begin maintenance therapy for ≥2 years or until disease progression, death, intolerance, withdrawal for other reasons, or the study's termination/completion.

Autologous BCMA-directed CAR-T cells, infusion intravenously at a target dose of 2.0-4.0 x 10^6 anti-BCMA CAR+T cells/kg.

achieving MRD-negative, as determined by NGS/NGF

Progression free survival is defined as the time from the date of diagnosis to the date of first documented PD, as defined in the IMWG criteria, or death due to any cause, whichever occurs first

CR or better is defined as percentage of participants who achieve a CR response or Stringent Complete Response (sCR) response accoording to the IMWG criteria