A Study to Examine the Effects of Novel Therapy Linvoseltamab in Combination With Other Cancer Treatments for Adult Participants With Multiple Myeloma That is Resistant to Current Standard of Care Treatments

Must have received: systemic anti-myeloma therapy

RRMM with progression following at least 3 lines of therapy, or at least 2 lines of therapy and either prior exposure to at least 1 anti-CD38 antibody, 1 immunomodulatory imide drug (IMiD) and 1 Proteasome Inhibitor (PI), or double-refractory to 1 PI and 1 IMiD, or the combination of 1 PI and 1 IMiD

Must have received: systemic anti-myeloma therapy

RRMM with progressive disease and received at least 3 lines of therapy including exposure to at least 1 anti-CD38 antibody, 1 IMiD, and 1 PI or triple-class refractory disease (anti-CD38 antibody, IMiD, PI)

Must have received: systemic anti-myeloma therapy

Progressive RRMM in participants with triple-class refractory disease (anti-CD38 antibody, IMiD, PI) after at least 3 lines of therapy

Must have received: systemic anti-myeloma therapy

Progressive RRMM after at least 3 lines of therapy including exposure to at least 1 anti-CD38 antibody, 1 IMiD, and 1 PI

Cannot have received: allogeneic stem cell transplant

History of allogeneic stem cell transplantation, as described in the protocol

Cannot have received: autologous stem cell transplant

History of autologous stem cell transplantation, as described in the protocol

Cannot have received: T cell-based immunotherapy directed against BCMA (bispecific antibodies, BiTEs, BCMA CAR-T cells)

Exception: BCMA antibody-drug conjugates are not excluded

Prior treatment with a T cell-based immunotherapy directed against B-Cell Maturation Antigen (BCMA) bispecific antibodies and Bispecific T-cell Engagers (BiTEs), and BCMA Chimeric Antigen Receptor (CAR) T cells (Note: BCMA antibody-drug conjugates are not excluded)

Cannot have received: BCMA-directed CAR T-cell therapy

Exception: Cohort 2: Dose expansion: Prior treatment with a BCMA-directed CAR T-cell therapy will not be exclusionary if completed at least 12 weeks prior to first study treatment

Cohort 2: Dose expansion: Prior treatment with a BCMA-directed CAR T-cell therapy will not be exclusionary if completed at least 12 weeks prior to first study treatment

Cannot have received: lenalidomide (lenalidomide)

Exception: Known malabsorption syndrome or pre-existing gastrointestinal (GI) condition that may impair absorption of lenalidomide; delivery of lenalidomide via nasogastric tube or gastrostomy tube is not allowed

Cohort 3: Known malabsorption syndrome or pre-existing gastrointestinal (GI) condition that may impair absorption of lenalidomide; delivery of lenalidomide via nasogastric tube or gastrostomy tube is not allowed

Cannot have received: bortezomib (bortezomib)

Exception: Peripheral neuropathy grade ≥2

Cohort 4: Peripheral neuropathy grade ≥2

Cannot have received: pomalidomide (pomalidomide)

Exception: Known malabsorption syndrome or pre-existing GI conditions that may impair absorption of pomalidomide; delivery of pomalidomide via nasogastric tube or gastrostomy tube is not allowed

Cohort 5: Known malabsorption syndrome or pre-existing GI conditions that may impair absorption of pomalidomide; delivery of pomalidomide via nasogastric tube or gastrostomy tube is not allowed

Cannot have received: anti-LAG-3 agent

Cohort 7: Prior treatment with anti-Lymphocyte Activation Gene 3 (LAG-3) agents

Cannot have received: anti-PD-1 agent

Cohort 8: Prior treatment with anti-PD-1 or anti-PD-L1 agents

Cannot have received: anti-PD-L1 agent

Cohort 8: Prior treatment with anti-PD-1 or anti-PD-L1 agents

Cannot have received: solid organ transplant

Cohort 7: Prior solid organ transplant; Cohort 8: Prior solid organ transplant

Cannot have received: cevostamab or FcRH5-targeted agent (cevostamab)

Cohort 10: Prior treatment with cevostamab or another agent with the same target [Fragment crystallizable Receptor-like 5 (FcRH5)]