• Subject has a confirmed diagnosis of multiple myeloma as specified by the International Myeloma Working Group criteria and must have measurable disease as defined by at least one of the following criteria:

• Serum monoclonal protein ≥ 0.5 g/dL

• ≥200 mg of monoclonal protein in the urine on 24-hour electrophoresis

• Serum immunoglobulin free light chain: involved FLC ≥ 10 mg/dL (≥ 100 mg/L) AND abnormal serum immunoglobulin kappa to lambda free light chain ratio

• MRD positivity in peripheral blood by flow cytometry.

• Subject previously received treatment with Carfilzomib.

• Subject is ≥18 years of age at the time of signing the informed consent form.

• Subject has an ECOG performance status of \< 2.

• Subjects must have completed any induction therapy and have achieved less than a CR.

• Subject has a life expectancy of \>12 weeks.

‣ Absolute neutrophil count (ANC) ≥1000 cells/mm3 (≥500 for patients with bone marrow biopsy displaying \>50% involvement by myeloma)

⁃ Platelets count ≥ 50,000/mm3 (≥ 30,000 for patients with bone marrow biopsy displaying \>50% involvement by myeloma)

⁃ Hemoglobin \> 9.0 g/dL

⁃ Serum SGOT/AST \<3.0 x upper limits of normal (ULN)

⁃ Serum SGPT/ALT \<3.0 x upper limits of normal (ULN)

⁃ Serum total bilirubin \<1.5 x ULN

• Subject must have a MUGA scan or echo with LVEF ≥40% within 6 months of enrollment.

• Females of childbearing potential (FCBP) must have a negative serum pregnancy test should be done within 7 days of treatment initiation and a negative urine pregnancy test within the 24 hours prior to the first study drug administration

• FCBP and male subjects who are sexually active with FCBP must agree to use 2 highly effective concomitant methods of contraception including a male condom during the study and for 90 days following the last dose of study treatment

• Male subjects must agree to not donate sperm while taking carfilzomib and for 90 days after the last dose of carfilzomib.