CD38 and plasma cell myeloma: Felzartamab is a recombinant fully human monoclonal CD38 antibody (IgG1) derived from a proprietary antibody phage library, initially developed for the treatment of multiple myeloma, and currently being evaluated in autoimmune disease (membranous nephropathy; ClinicalTrils.gov Identifier: NCT04145440; NCT04733040).