A Clinical Trial of Four Medicines (Elranatamab Plus Carfilzomib and Dexamethasone or Maplirpacept) in People With Relapsed Refractory Multiple Myeloma

Inclusion Criteria: * Prior diagnosis of multiple myeloma as defined by IMWG criteria. * Measurable disease based on IMWG criteria as defined by at least 1 of the following: * Serum M-protein ≥0.5 g/dL. * Urinary M-protein excretion ≥200 mg/24 hours. * Serum immunoglobulin FLC ≥10 mg/dL (≥100 mg/L) AND abnormal serum immunoglobulin kappa to lambda FLC ratio (\<0.26 or \>1.65). * Part 1: Received at least 1 but not more than 3 prior lines of therapy for multiple myeloma (induction therapy followed by stem cell transplant and consolidation/maintenance therapy will be considered as 1 line of therapy). * Part 2: Received at least 3 prior lines of therapy for multiple myeloma who are refractory to at least one IMiD, one PI and one anti-CD38 antibody. * ECOG performance status 0-1. * Resolved acute effects of any prior therapy to baseline severity or CTCAE Grade ≤1. * Not pregnant or breastfeeding and willing to use contraception. Exclusion Criteria: * Plasma cell leukemia, Smouldering MM, Waldenströms macroglobulinemia, Amyloidosis, POEMS Syndrome, Primary refractory MM * Impaired cardiovascular function or clinically significant cardiovascular diseases. * Participants with any active, uncontrolled bacterial, fungal, or viral infection. * Stem cell transplant within 12 weeks prior to enrollment, or active graft versus host disease. * Any other active malignancy within 3 years prior to enrollment, except for adequately treated basal cell or squamous cell skin cancer, or c…