CD38 and plasma cell myeloma: Of note, all five post-BCMA patient multiple myeloma samples (HTB-700, HTB-718, HTB-955.13, HTB-2505, and HTB-1337) had CD38 expression more than 6-fold greater than on non-MM cells, supporting our hypothesis that post-Dara patients relapsed after BCMA therapy have sufficient CD38 expression to respond to SAR442257 (Supplementary Fig. S3).