The purpose of the study is to evaluate safety and tolerability of the combination of cevostamab plus elranatamab and also determine the recommended Phase II regimen (RP2R) for the study treatment. The study consists of a safety lead-in stage, and an expansion stage.
Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1
Diagnosis of R/R MM per IMWG criteria
For female participants of childbearing potential: agreement to remain abstinent or use contraception
For male participants: agreement to remain abstinent or use a condom
Prior treatment with cevostamab or another agent targeting fragment crystallizable receptor-like 5 (FcRH5)
Prior treatment with elranatamab
Prior allogeneic stem cell transplantation (SCT)
Absolute plasma cell count exceeding 500 per milliliter (mL) or 5% of the peripheral blood white cells