Talquetamab & Lenalidomide as Post Stem Cell Transplant Maintenance in Multiple Myeloma

Multiple myeloma (MM) is a heterogenous plasma cell malignancy characterized by clonal proliferation of plasma cells and organ damage. Autologous transplantation with high dose chemotherapy is the standard of care in frontline treatment of eligible patients with MM.

Inclusion Criteria: 1. Participants must have had a confirmed diagnosis of symptomatic multiple myeloma according to according to IMWG diagnostic criteria. 2. Measurable disease at the time of myeloma diagnosis Measurable disease is defined as measurable M protein in the serum (≥ 0.5g/dL) or urine (≥ 200 mg/24h) or serum free light chain assay (defined as dFLC ≥ 10 mg/dL \[≥ 100 mg/L\]; difference between involved and uninvolved free light chain) at the time of diagnosis. Participants with smoldering myeloma are not eligible until they have progressed to symptomatic myeloma. Participants with purely non-secretory MM at the time of diagnosis as measured by electrophoresis and immunofixation and the absence of Bence Jones proteins in the urine are not eligible. 3. Age \>18 years. 4. Patients who have already received transplant should have undergone autologous stem cell transplant with Melphalan 140 mg/m2 within 12 months of start of induction therapy of multiple myeloma and are within day +60-120 post-transplant. Patients who have not already received transplant must have begun induction therapy within 12 months prior to the planned date of transplant. 5. Participants must not be refractory to lenalidomide 6. Participants must not have progressive disease at any time prior to registration 7. Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0 or 1. 8. Have clinical laboratory values meeting the following criteria during the Screening Phase and also at start of administration of study treatment: \- Hemoglobin: ≥ 8 g/dL (≥ 4.96 mmol/L; without transfusion support or erythropoietin use within 7 days before the laboratory test) \- Platelets: ≥ 75×109/L in participants in whom \6 months prior to full study screening and considered to have a very low risk of recurrence, or e). History of localized prostate cancer and receiving androgen deprivation therapy and considered to have a very low risk of recurrence. f) Breast cancer: adequately treated lobular carcinoma in situ or ductal carcinoma in situ, or history of localized breast cancer and receiving antihormonal agents and considered to have a very low risk of recurrence g) Other malignancy that is considered cured with minimal risk of recurrence. 9\. Stroke, transient ischemic attack, or seizure within 6 months prior to signing ICF. 10\. Participant is pregnant, breast-feeding, or planning to become pregnant while enrolled in this study or within 100 days after the last dose of study treatment. 11\. Participant plans to father a child while enrolled in this study or within 100 days after the last dose of study treatment. 12\. Presence of the following cardiac conditions: 1. New York Heart Association stage III or IV congestive heart failure 2. Myocardial infarction or coronary artery bypass graft ≤6 months prior to randomization 3. Uncontrolled cardiac arrhythmia or clinically significant ECG abnormalities 4. History of clinically significant ventricular arrhythmia or unexplained syncope, not believed to be vasovagal in nature or due to dehydration 5. History of severe non-ischemic cardiomyopathy 13\. Any of the following: a. Known to be seropositive for human immunodeficiency virus 1. Active hepatitis B infection (ie, HBsAg or HBV-DNA positive). In the event the infection status is unclear, quantitative viral levels are necessary to determine the infection status see Section 0 for further required assessments. 2. Active hepatitis C infection as measured by positive HCV-RNA testing. Participants with a history of HCV antibody positivity must undergo HCV-RNA testing. If a participant with history of chronic hepatitis C infection (defined as both HCV antibody and HCV-RNA positive) completed antiviral therapy and has undetectable HCV-RNA for at least 12 weeks following the completion of therapy, the participant is eligible for the study. 14\. Major surgery within 2 weeks prior to the start of administration of study treatment, or will not have fully recovered from surgery, or has major surgery planned during the time the participant is expected to be treated in the study or within 2 weeks after administration of the last dose of study treatment. NOTE: Participants with planned surgical procedures to be conducted under local anesthesia may participate. Kyphoplasty or vertebroplasty are not considered major surgery. If there is a question whether a procedure is considered a major surgery, the investigator must consult with the study principal investigator and resolve any issues before enrolling a participant in the study. 15\. Concurrent medical or psychiatric condition or disease that is likely to interfere with study procedures or results, or that in the opinion of the investigator would constitute a hazard for participating in this study, such as: 1. Uncontrolled diabetes 2. Acute diffuse infiltrative pulmonary disease 3. Evidence of active systemic viral, fungal, or bacterial infection, requiring systemic antimicrobial therapy 4. Active autoimmune disease requiring systemic immunosuppressive therapy within 6 months before start of study treatment. EXCEPTION: Participants with vitiligo, controlled type I diabetes, and prior autoimmune thyroiditis that is currently euthyroid based on clinical symptoms and laboratory testing are eligible regardless of when these conditions were diagnosed. 5. Disabling psychiatric conditions (e.g., alcohol or drug abuse), severe dementia, or altered mental status 6. Any other issue that would impair the ability of the participant to receive or tolerate the planned treatment at the investigational site, to understand informed consent or any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant (e.g., compromise the well-being) or that could prevent, limit, or confound the protocol-specified assessments All subject files must include supporting documentation to confirm subject eligibility.