Inclusion Criteria:

          -  Documented diagnosis of multiple myeloma according to International Myeloma Working
             Group (IMWG) diagnostic criteria

          -  Participants must be relapsed or refractory to established therapies with known
             clinical benefit in relapsed/refractory multiple myeloma (MM) or be intolerant of
             those established MM therapies, and a candidate for talquetamab treatment in the
             opinion of the treating physician. Prior lines of therapy must include a proteasome
             inhibitor (PI), an immunomodulatory drug (IMiD) and an anti-CD38 antibody in any order
             during the course of treatment. Participants who could not tolerate a PI,
             immunomodulatory drugs or anti-CD38 antibody are allowed

          -  Eastern cooperative oncology group (ECOG) performance status grade of 0 or 1 at
             screening and immediately before the start of study treatment administration

          -  Women of childbearing potential must have a negative pregnancy test at screening and
             within 24 hours prior to the first dose of study treatment using highly sensitive
             pregnancy test either serum (Beta-human chorionic gonadotropin [Beta-hCG]) or urine

          -  Participants (or a legally acceptable representative) must sign an informed consent
             form (ICF) indicating that he or she understands the purpose of, and procedures
             required for, the study and is willing to participate in the study. Consent is to be
             obtained prior to the initiation of any study-related tests or procedures that are not
             part of standard-of-care for the participant's disease

        Exclusion Criteria:

          -  Toxicities from previous anticancer therapies that have not resolved to baseline
             levels or to Grade 1 or less except for alopecia or peripheral neuropathy

          -  Received a cumulative dose of corticosteroids equivalent to >=140 milligrams (mg) of
             prednisone within the 14-day period before the first step-up dose of study treatment
             (does not include pretreatment medication)

          -  Central nervous system involvement or clinical signs of meningeal involvement of
             multiple myeloma. If either is suspected, whole brain magnetic resonance imaging (MRI)
             and lumbar cytology are required during screening

          -  Pulmonary compromise requiring supplemental oxygen use to maintain adequate
             oxygenation

          -  Known allergies, hypersensitivity, or intolerance to the excipients of talquetamab