Compared to the control group, overall stem cell collection was impaired in the Isa-VRd group.In an investigation exploring the impaired mobilization mechanisms of CD34+ cells caused by anti-CD38 monoclonal antibodies, 34 MM patients eligible for transplantation received four cycles of VTd (n=14), Dara-VCd (daratumumab + bortezomib + cyclophosphamide + dexamethasone) (n=9), or Isa-KRd (isatuximab + carfilzomib + lenalidomide + dexamethasone) (n=11) before mobilization (31). Here, CD38 is linked to Miyoshi myopathy.