 The most recent multiple myeloma MM treatment regimen should contain daratumumab DARA and subjects must have progressed on DARA while on this regimen. Stage 1 A cohort of 18 subjects will be enrolled to determine the preliminary efficacy of DARA plus DURVA. Once the 18 subjects have been enrolled, an interim analysis for futility purpose will be conducted to determine if the study can proceed to Stage 2. 