Carfilzomib and Dexamethasone in Treating Patients With Multiple Myeloma Who Previously Underwent a Stem Cell Transplant

PRIMARY OBJECTIVES: I. To assess the complete response (CR) rate with carfilzomib and dexamethasone consolidation following an upfront single stem cell transplant (SCT). SECONDARY OBJECTIVES: I. To assess the toxicity of carfilzomib and dexamethasone when used as consolidation therapy in patients post SCT. II. To determine the progression free rate at 1 and 2 years post SCT. III. To evaluate progression-free survival and overall survival. TERTIARY OBJECTIVES: I. To determine the proportion of patients achieving a minimal residual disease (MRD) negative status. II. To assess the HevyLite assay prior to and during treatment. OUTLINE: Patients receive carfilzomib intravenously (IV) over 30 minutes and dexamethasone orally (PO) on days 1, 2, 15, and 16. Treatment repeats every 28 days for 6 courses in the absence of disease progression or unacceptable toxicity. After completion of study therapy, patients are followed up every 3 months for 3 years and then every 6 months for 2 years.