RecruitingPhase 2Drug trialStudy of IgPro20 to Prevent Infection in People With Multiple Myeloma and HypogammaglobulinemiaThe main purpose of this study is to see if IgPro20 can prevent infection in people with multiple myeloma (MM) who have hypogammaglobulinemia from receiving bispecific monoclonal antibodies (BsAbs).