TNFSF13B and Miyoshi myopathy: In MM, two phase II studies, conducted in US and Japanese cohorts, failed to show any clinical improvement in progression free survival (145–147), probably for high BAFF concentrations in RRMM patients or the induction of compensatory pathways via APRIL/BCMA engagement (148–151), suggesting the need to combine tabalumab with anti‐APRIL antibody or TACI‐Fc fusion protein, a potent inhibitor of both BAFF and APRIL, to augment clinical efficacy in RRMM.