The addition of XVd to the treatment landscape for previously treated MM provides a novel, convenient regimen that appears to be noninferior to other top 5 regimens in both 2L and 3L+ settings, and allows for a fourth (after IMiD, PI, and anti-CD38 mAb) novel mechanism to be leveraged against recurrent MM. This evidence concerns the gene CD38 and Miyoshi myopathy.