Study to Assess for Measurable Residual Disease (MRD) in Multiple Myeloma Patients

Inclusion Criteria: * Males and females \> 18 years of age * ECOG performance status less than or equal to 2 (Karnofsky \> 60%) * Patients with a diagnosis of multiple myeloma who have undergone initial treatment, with or without autologous stem cell transplant, and currently treated with single-agent maintenance therapy (lenalidomide, pomalidomide, bortezomib, daratumumab, or ixazomib) for a duration of at least 1 year. The 1 year duration can include time spent receiving at least 8 cycles of doublet or triplet induction regimens OR multi-agent post-transplant maintenance prior to conversion to single agent maintenance therapy. * Patients must have had their most recent bone marrow testing within the last 2 years and negative for MRD by flow cytometry (with a sensitivity of at least 10-5) or by NGS with a sensitivity of at least 10-5. * Patients must have achieved a CR (CR) by IMWG consensus response criteria. For patients with a persistent low level paraprotein ('M-spike'), mass spectrometry may be used to determine if the paraprotein is significant or not. Results of mass spectrometry may be used to supercede results of serum protein electrophoresis. * Patients must have a most recent PET/CT within the last 1.5 years without evidence of myeloma disease. * Must have baseline bone marrow sample that can be used for clonality identification for NGS and mass spectrometry if not already performed. * Willing and able to undergo a bone marrow biopsy and aspiration. * Ability to …