• Documented newly diagnosed multiple myeloma

• a. At least 25% of patients accrued should be high risk as defined by IMWG or mSMART criteria.

• Patient should be deemed transplant eligible.

• Patients may not have had more than 1 cycle of prior induction therapy. If a patient has had 1 cycle of prior multiple myeloma therapy, the patient must have had documented measurable disease prior to initiation of cycle 1.

• Subjects must satisfy the following criteria to be enrolled in the study:

∙ Subject is ≥ 18 years of age at the time of signing the informed consent form (ICF).

‣ Subject must understand and voluntarily sign an ICF prior to any study-related assessments/procedures being conducted.

‣ Subject is willing and able to adhere to the study visit schedule and other protocol requirements.

• Subjects must have a documented diagnosis of MM and have measurable disease defined as:

∙ M-protein (serum and/or urine protein electrophoresis (sPEP or uPEP)): sPEP≥0.5 g/dL or uPEP ≥ 200 mg/24 hours and/or

‣ Light chain MM without measurable disease in the serum or urine: serum immunoglobulin free light chain ≥ 10 mg/dL (100 mg/L) and abnormal serum immunoglobulin kappa lambda free light chain ratio

• Eastern Cooperative Oncology Group (ECOG) performance status score of 0, 1 or 2.

• A female of childbearing potential (FCBP) is a female who: 1) has achieved menarche at some point, 2) has not undergone a hysterectomy or bilateral salpingectomy, or 3) has not been naturally postmenopausal (amenorrhea following cancer therapy does not rule out childbearing potential) for at least 24 consecutive months (ie, has had menses at any time in the preceding 24 consecutive months) and must:

• a. Have two negative pregnancy tests as verified by the Investigator prior to starting study treatment. She must agree to ongoing pregnancy testing during the course of the study, and after end of study treatment. This applies even if the subject practices true abstinence from heterosexual contact.

• Either commit to true abstinence from heterosexual contact (which must be reviewed on a monthly basis and source documented) or agree to use, and be able to comply with two forms of contraception: one highly effective, and one additional effective (barrier) measure of contraception without interruption 28 days prior to starting investigational product, during the study treatment (including dose interruptions), and for at least 28 days after the last dose of iberdomide.

• Male subjects must:

• a. Male subjects must practice complete abstinence (True abstinence is acceptable when this is in line with the preferred and usual lifestyle of the subject. Periodic abstinence \[e.g. calendar, ovulation, symptothermal or post-ovulation methods\] and withdrawal are not acceptable methods of contraception.) or agree to use a condom during sexual contact with a pregnant female or a FCBP while taking iberdomide, during dose interruptions and for at least 28 days following the last dose of iberdomide even he has undergone a successful vasectomy.

⁃ Males must agree to refrain from donating sperm while on study treatment, during dose interruptions and for at least 28 days following last dose of study treatment.

⁃ All subjects must agree to refrain from donating blood while on study treatment, during dose interruptions and for at least 28 days following the last dose of study treatment.

⁃ All male and female subjects must follow all requirements defined in the Pregnancy Prevention Program.

• Note: A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. A high follicle stimulating hormone (FSH) level in the postmenopausal range may be used to confirm a post-menopausal state in women not using hormonal contraception or hormonal replacement therapy. However, in the absence of 12 months of amenorrhea, a single FSH measurement is insufficient.