A Phase IV Study to Learn About the Study Medicine Called Elranatamab in People With Multiple Myeloma That is Not Responding to Four or More Standard Treatments or Has Come Back After Several Standard Treatments

This is a Phase 4, multicenter, open-label, single-arm study evaluating the safety and efficacy of elranatamab monotherapy in adult participants with relapsed or refractory multiple myeloma in India. Eligible participants must have received at least four prior lines of therapy, including an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 antibody. All enrolled participants will receive elranatamab; there is no comparator or control arm. Approximately 100 participants are planned to be enrolled across approximately 10 study sites in India. Study assessments will include evaluation of disease response and monitoring of adverse events in accordance with the study protocol.

Inclusion Criteria Participants are eligible to be included in this study only if all of the following criteria apply: Age and Sex: 1. 18 years of age or older (or the minimum age of consent in accordance with local regulations) at screening. • Refer to Appendix 4 for reproductive criteria for male (Section 10.4.1) and female (Section 10.4.2) participants. Disease Characteristics: 2. Prior diagnosis of MM as defined according to IMWG criteria and currently having at least 1 of the following * Serum M-protein ≥0.5 g/dL by SPEP * Urinary M-protein excretion ≥200 mg/24 hours by UPEP * Serum immunoglobulin FLC ≥10 mg/dL (≥100 mg/L) AND abnormal serum immunoglobulin kappa to lambda FLC ratio (\1.65). 3. Previously received at least four prior therapies, including an immunomodulatory agent, a proteasome inhibitor and an anti-CD38 antibody. Other Inclusion criteria: 4. Must sign an informed consent form indicating that the participant understands the purpose and procedures required for the study treatment plan; required concomitant medications, laboratory test and are willing to participate. 5. ECOG PS 0 or 1 5.2. Exclusion Criteria Participants are excluded from the study if any of the following criteria apply: Medical Conditions: 1. Any of the conditions mentioned below: * Plasma cell leukemia (anytime prior study entry) , Smoldering MM (at study entry), Waldenström's macroglobulinemia (anytime prior study entry), Amyloidosis (anytime prior study entry). * POEMS Syndrome. * Known CNS involvement or clinical signs of myelomatous meningeal involvement. * History of stem cell transplant within 12 weeks prior to enrollment. * Active GVHD (other than Grade 1 skin involvement), or GVHD requiring treatment. * Participants with any other active malignancy within 3 years prior to enrollment, except for adequately treated basal cell or squamous cell skin cancer, or carcinoma in situ of the cervix, Bowen's disease. * Ongoing Grade 2 or higher peripheral sensory or motor neuropathy. * History of GBS or GBS variants, or history of any Grade ≥3 peripheral motor polyneuropathy. 2. Known or suspected hypersensitivity to elranatamab or any other study interventions or any of their excipients. 3. Any medical or psychiatric condition including any active suicidal ideation in the past year or suicidal behavior in the past 5 years or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study. Prior/Concomitant Therapy: 4. Previous treatment with an anti-BCMA bispecific antibody or a CD3-redirecting therapy. 5. Cumulative dose of corticosteroids equivalent to ≥140 mg of prednisone within the 14-day period before the first dose of study intervention. 6. Any anti-myeloma drug therapy within 14 days of the first dose of study intervention (includes dexamethasone). Bisphosphonate use permitted. 7. Live attenuated vaccine must not be administered within 4 weeks of the first dose of study intervention. Prior/Concurrent Clinical Study Experience: 8. Previous administration with an investigational product (drug or vaccine) within 30 days (or as determined by the local requirement) or 5 half-lives preceding the first dose of study intervention used in this study (whichever is longer). A participant may be eligible even if they are in the follow-up phase of an investigational study if they meet the criterion for time elapsed from previous administration of investigational product. Cases must be discussed with sponsor's medical monitor to judge eligibility. Diagnostic Assessments: 9. Hepatic dysfunction defined as having any 1 of the following, which may be confirmed by a single repeat test, if necessary: * Total bilirubin \>2 × ULN (except for Gilbert's syndrome, direct bilirubin \>3 × ULN is exclusionary) * AST \>2.5 × ULN * ALT \>2.5 × ULN 10. Hematologic abnormalities defined as any 1 of the following,: * ANC \