• Patients must have a documented diagnosis of multiple myeloma defined by the International Myeloma Working Group Criteria (IMWG).5 Patients at initial diagnosis must have had a serum M-protein ≥ 3 g/dL and/or bone marrow plasma cells ≥10%, and at least one of the following:

‣ Anemia: Hemoglobin ≤10 g/dL, or

⁃ Renal failure: serum creatinine ≥ 2.0 mg/dL, or

⁃ Hypercalcemia: Ca ≥10.5 mg/dL, or

⁃ Lytic bone lesions on X-ray, CT, or Positron emission tomography/Computed Tomography (PET/CT), or

⁃ ≥ 2 focal lesions on spinal magnetic resonance imaging (MRI), or

⁃ ≥ 60% bone marrow plasma cells, or Involved/un-involved serum free light chain ratio ≥ 100. Age ≥18 years of age on day of signing informed consent.

• Patients must have had a bone marrow (BM) biopsy proven plasma cell myeloma harboring the t(11;14) translocation as reported by a Clinical Laboratory Improvement Amendments (CLIA) certified assay (i.e. local fluorescence in situ hybridization (FISH) testing). BM biopsy can be performed at time of enrollment or documented FISH results (i.e. original FISH report) can be used.

• Must have Relapsed or Relapsed and Refractory Multiple Myeloma. Patients must have documented evidence of having received two prior lines of therapy and be refractory to, not a candidate for (ineligible), or intolerant of at least one immunomodulatory (IMiD), one proteasome inhibitor, and one anti-cluster of differentiation 38 (anti-CD38) monoclonal antibody-based treatments.

• Documented measurable disease based on the IMWG guidelines within the 4 weeks prior to registration defined by any one of the following criteria:

‣ Serum monoclonal protein ≥ 0.5 g/dl

⁃ Urine monoclonal protein \>200 mg/24 hour

⁃ Serum immunoglobulin free light chain \>10 mg/dL AND abnormal kappa/lambda ratio

⁃ Bone marrow plasma cells ≥ 30%

⁃ A measurable lesion on PET/CT or MRI ≥ 2 cm

• Be ≥ 18 years of age on day of signing informed consent

• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of ≤ 3 (Appendix A)

• Adequate organ function as evidenced by the following laboratory parameters within 4 weeks of C1D1:

• Hematologic:

⁃ Absolute neutrophil count (ANC) 1000/microliter (mcL) (granulocyte-colony stimulating factor (G-CSF) allowed)

⁃ Platelets ≥ 50,000/mcL (transfusions and stimulators permitted); in patients with \>50% bone marrow plasma cells, platelets ≥ 30,000/mcL

⁃ Hemoglobin ≥ 8 g/dL (transfusions permitted)

‣ Non-hematologic:

⁃ Serum creatinine ≤ 1.5 X ULN (except if due to myeloma) or calculated creatinine clearance (CrCl)/Estimated glomerular filtration rate (eGFR) (by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Modification of Diet in Renal Disease (MDRD), or Cockcroft-Gault) ≥ 15 mL/min/1.73 m2

⁃ Serum total bilirubin ≤ 1.5 X ULN or direct bilirubin ≤ ULN for patients with total bilirubin levels \> 1.5 ULN (except patients with Gilbert's syndrome who must have a total bilirubin of \< 3 X ULN)

⁃ Aspartate transaminase (SGOT) and alanine transaminase (SGPT) ≤ 2.5 X ULN

• Female patients of childbearing potential must have a negative serum pregnancy test at Screening. Female patients of childbearing potential and fertile male patients who are sexually active with a female of childbearing potential must use highly effective methods of contraception throughout the study and for 90 days following the last dose of study treatment.

• Willing and able to provide written informed consent in accordance with federal, local, and institutional guidelines. The patient must provide informed consent prior to the first screening procedure.