A Trial to Learn if Linvoseltamab is Safe and Works in Adults With Relapsed or Refractory Systemic Light Chain Amyloidosis (AL Amyloidosis)

Key Inclusion Criteria: 1. Confirmed diagnosis of AL amyloidosis, as described in the protocol 2. Measurable disease as defined by serum difference between involved and uninvolved free light chains (dFLC) concentration, as described in the protocol 3. Previously treated after at least 1 prior therapy and requiring further treatment as assessed by the Investigator 4. N-terminal pro b-type natriuretic peptide (NT-proBNP) ≤8500 ng/L during screening 5. Adequate hepatic, hematologic, renal, and cardiac function, as described in the protocol 6. Eastern Cooperative Oncology Group (ECOG) performance score ≤2 at screening Key Exclusion Criteria: 1. History of other non-AL amyloidosis 2. Greater than 60% plasmacytosis on a bone marrow biopsy and/or aspirate during screening 3. Presence of lytic bone lesion(s) or extramedullary plasmacytoma on imaging during screening 4. Myocardial infarction within the past 6 months prior to the first screening visit 5. Known active infection requiring hospitalization or treatment with IV anti-infectives within 28 days of first administration of study drug NOTE: Other protocol defined inclusion/exclusion criteria apply