To address these questions, we (i) analyzed the competition between daratumumab and isatuximab for CD38 binding using MM cell lines and BM plasma cells, (ii) determined the kinetics of CD38 surface recovery after antibody binding and removal, and (iii) compared the functional effects of both antibodies on direct apoptosis induction, cell migration, and adhesion. This evidence concerns the gene CD38 and Miyoshi myopathy.