Inclusion Criteria:

          -  Histologically confirmed diagnosis of multiple myeloma (International Classification
             of Disease (ICD-10) code: C90.0)

          -  Previous exposure to at least one proteasome inhibitors (PI) and lenalidomide (or
             candidacy for isatuximab as per updated Food and Drug Administration (FDA) package
             insert information in the future)

          -  Planned or current isatuximab-containing therapy. Patients receiving isatuximab as
             part of a clinical trial are eligible for this study if allowed by the trial sponsor.

               -  For ease of registration, patients will be allowed to enroll at any point after
                  the decision is made to initiate isatuximab (with the understanding that their
                  initial doses will be standard of care (SOC), including the first 2 doses for all
                  patients). However, rapid infusion (RI) isatuximab will only be administered to
                  participants who have not had infusion-related reactions (iRRs) during >= 2
                  consecutive prior doses of SOC isatuximab

          -  Ability to understand a written informed consent form (ICF) document, and the
             willingness to sign the ICF document

        Exclusion Criteria:

          -  Age < 18

          -  Body weight > 70 kilograms (kg) at the time of any RI isatuximab dose

          -  Current pregnancy or (if of reproductive age) unwillingness to follow contraception
             requirements as per the FDA package insert

          -  New York Heart Association Stage IV heart disease, i.e. unable to carry on any
             physical activity without discomfort or symptoms of heart failure (as per study
             investigator)

          -  Any medical condition, including mental illness or substance abuse, deemed by the
             principal investigator to interfere with the ability to provide consent or cooperate
             with study procedures