This study looks at how well two different treatments work for people with relapsed or refractory multiple myeloma, a type of blood cancer. Multiple myeloma happens when abnormal plasma cells build up in the bone marrow, which is the soft tissue inside bones. The study compares two treatments: JNJ-79635322 and a special type of medicine called a bispecific antibody that targets BCMA (B-cell maturation antigen) and CD3. Participants must have tried at least three other treatments before, including specific types of medicines like proteasome inhibitors and immunomodulatory drugs. They also need to have measurable disease and not be too sick from previous treatments.

• The study requires several visits and tests to monitor health and response to the treatments.
• Participants should not have recent major surgeries or certain infections like active hepatitis.
• Participants may receive compensation for their time and travel expenses.