Five patients in Part 1 discontinued treatment due to an AE, with 2 reported as myelodysplastic syndrome possibly related to pomalidomide, 1 due to progressive multifocal leukoencephalopathy also attributed to pomalidomide, 1 secondary to increase in alanine transaminase possibly related to belamaf and 1 due to grade 4 decrease in best corrected visual acuity (BCVA) definitely related to belamaf. This evidence concerns the gene GPT and progressive multifocal leukoencephalopathy.