• Documented informed consent of the participant and/or legally authorized representative.

⁃ Assent, when appropriate, will be obtained per institutional guidelines

• Age: \>= 18 years

• Eastern Cooperative Oncology Group (ECOG) =\< 2

• Diagnosis of multiple myeloma

• Subject must have received at least 4 prior lines of therapy, including an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 antibody

• Receipt of commercially available idecabtagene vicleucel (Abecma) according to FDA approved US Prescribing Information. Note: Patients who received non-conforming Abecma who were originally prescribed Abecma according to the FDA approved label may be considered for inclusion per the investigators discretion. Subject must be between day 30 and day 90 post receipt of idecabtagene vicleucel

• Subject must have experienced at least a stable disease in response to idecabtagene vicleucel

• Fully recovered from the acute toxic effects (except alopecia) to =\< grade 1 to prior anti-cancer therapy, including idecabtagene vicleucel

• Absolute neutrophil count (ANC) \>= 1,500/mm\^3 without the use of filgrastim in the previous 3 days (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated)

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Platelets \>= 75,000/mm\^3 without platelet transfusion in the previous 3 days. (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated)

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Total bilirubin =\< 1.5 X upper limit of normal (ULN) (unless has known Gilbert's disease) (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated).

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Aspartate aminotransferase (AST) =\< 3 x ULN (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated).

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Alanine transaminase (ALT) =\< 3 x ULN (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated).

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Alkaline phosphatase =\< 5 x ULN (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated)

• Creatinine clearance of \>= 50 mL/min per 24 hour urine test or the Cockcroft-Gault formula (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated).

⁃ Two repeat tests are allowed. If the repeat test satisfies criteria, the participant may enroll provided all other criteria are met

• Oxygen saturation \> 92% on room air (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated)

• Women of childbearing potential (WOCBP): negative urine or serum pregnancy test. If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required (To be performed within 14 days prior to day 1 of protocol therapy unless otherwise stated)

• Agreement by females of childbearing potential and males to follow the guidelines of the mezigdomide (CC-92480) pregnancy prevention plan