A Study to Evaluate the Safety, Pharmacokinetics, and Efficacy of Isatuximab in Patients With Multiple Myeloma

Primary Objective: * Part A: To evaluate the safety of SAR650984 (isatuximab) in patients with relapsed/refractory multiple myeloma (RRMM). * Part B: To evaluate the activity of SAR650984 (isatuximab) as assessed by overall response rate (ORR) in RRMM patients previously treated with daratumumab. Secondary Objectives: * Part A: * To determine the pharmacokinetics (PK) of SAR650984 (isatuximab) in patients with RRMM. * Part B: * To evaluate the safety of SAR650984 (isatuximab). * To evaluate the efficacy of SAR650984 (isatuximab) as assessed by duration of response (DOR), clinical benefit rate (CBR) and progression free survival (PFS). * To assess the pharmacokinetics (PK) of SAR650984 (isatuximab) and daratumumab at baseline. * To evaluate the immunogenicity of SAR650984 (isatuximab).