An Efficacy and Safety Study of bb2121 in Subjects With Relapsed and Refractory Multiple Myeloma and in Subjects With High-Risk Multiple Myeloma

Anti-myeloma bridging treatment is allowed for disease control while bb2121 is being manufactured for cohorts 1, 2a and 2b only. In Cohort 1b only, subjects will receive bridging therapy with 1 to 2 cycles of talquetamab, and initiate Lymphodepleting (LD) chemotherapy at least 14 days after the last dose of talquetamab.