• \>18 years of age

• Diagnosis of SMM for ≤5 years with measurable disease, defined as serum M protein:

• ≥1g/dL or urine M protein ≥200 mg/24 hours or involved serum FLC ≥100 mg/Land abnormal serum FLC ratio.

• BMPCs ≥10% and \<60%

• Presence of at least 2 high risk factors, including

‣ Serum M protein ≥2 g/dL,

⁃ BMPC \>20%

⁃ Serum involved/uninvolved FLC ratio \> 20

• ECOG performance status score of 0 or 1

• Subjects must meet the following laboratory parameters, per laboratory reference range (performed at most 15 days before cycle 1 day 1)

‣ Absolute neutrophil count ≥1.0 x 109/L (ie, ≥1000/μL)

⁃ Platelet count ≥75 x 109/L

⁃ Aspartate aminotransferase (AST) ≤2.5 x upper limit of normal (ULN)

⁃ Alanine aminotransferase (ALT) ≤2.5 x ULN

⁃ Total bilirubin ≤1.5 x ULN, except in subjects with congenital bilirubinemia,such as Gilbert syndrome (in which case direct bilirubin ≤2.0 x ULN is required)

• Subject must sign an informed consent form (ICF) or their legally acceptable representative must sign indicating that he or she understands the purpose of, and procedures required for the study and is willing to participate in the study.

• Women of childbearing potential must have a negative serum or urine pregnancy test at screening and before starting study drug. They must commit to continued abstinence from heterosexual intercourse or begin 2 acceptable methods of birth control (One highly effective method and one additional effective method) used at the same time, and continuing for at least 5 months after the last dose of Elranatamab. Women must also agree to notify pregnancy during the study.