After meeting the eligibility criteria and enrolling on the trial, patients will undergo leukapheresis for collection of autologous lymphocytes, which will be sent to BMS/Celgene manufacturing facilities. Once cells have been manufactured, patients will then proceed to lymphodepleting chemotherapy with cyclophosphamide 300mg/m^2 and fludarabine 30mg/m^2 for 3 consecutive days followed by the infusion of BCMA CAR T-cells at a target dose of 450 x10^6 cells. Maintenance lenalidomide, starting at 5mg a day for 21 days of a 28-day cycle will be initiated at a minimum of at least 30 days, but no later than 180 days after the CAR T-cell infusion and will continue until the patient reaches 12 months post CAR T-cell infusion and continue free of progression