A recombinant fusion protein of the extracellular domain of TNFRSF13B and the human IgG1-Fc (TACI-Ig) inhibited TNFRSF13B signalling and induced apoptosis of myeloma cells in vitro [47], and treatment using TACI-Ig was associated with some anti-tumour activities in multiple myeloma and Waldenström’s macroglobulinemia in a phase I/II trial [48]. Here, TNFRSF13B is linked to plasma cell myeloma.