Isatuximab With or Without Lenalidomide in Patients With High Risk Smoldering Multiple Myeloma (ISAMAR)

PRIMARY OBJECTIVE: \- To determine the rate of response according to the International Myeloma Working Group Criteria. SECONDARY OBJECTIVES: * To determine progression free survival (PFS) at 2 years. * To determine overall survival (OS). * To determine duration of response (DOR). * To determine the clinical benefit rate (CBR). * To evaluate safety of single agent treatment in this population * To evaluate safety of single agent treatment in this population. * To evaluate the immunogenicity of isatuximab. OUTLINE: Patients on single agent cohort receive isatuximab intravenously (IV) over 5 hours on day 1 of cycle 1, and over 3 hours thereafter on days 8, 15, and 22 of cycle 1, on days 1 and 15 of cycles 2-6, and on day 1 of subsequent cycles. Patients on Combination Cohort with Lenalidomide receive isatuximab as in single agent cohort plus Lenalidomide po 21/28 days during cycles 1-6 only. Treatment repeats every 28 days for up to 30 cycles in the absence of disease progression or unacceptable toxicity. Treatment repeats every 28 days for up to 30 cycles in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 6-12 months.