RecruitingPhase 2Drug trialA Study of Talquetamab for People With Multiple Myeloma Who Have Received BCMA CAR T-Cell TherapyThe researchers are doing this study to find out whether talquetamab is an effective treatment after BCMA CAR Tcell therapy for people with relapsed or refractory multiple myeloma. All participants in this study will have already received the BCMA CAR T-cell therapy ide-cel for their disease.