A Study Comparing JNJ-68284528, a CAR-T Therapy Directed Against B-cell Maturation Antigen (BCMA), Versus Pomalidomide, Bortezomib and Dexamethasone (PVd) or Daratumumab, Pomalidomide and Dexamethasone (DPd) in Participants With Relapsed and Lenalidomide-Refractory Multiple Myeloma

Inclusion criteria

• ✓. Hemoglobin \>=8 gram per deciliter (g/dL) (without prior RBC transfusion within 7 days before the laboratory test; recombinant human erythropoietin use is permitted);
• ✓. Absolute neutrophil count (ANC) \>=1 \* 10\^9 per liter (L) (without recombinant human granulocyte colony-stimulating factor \[G-CSF\] within 7 days and without pegylated G-CSF within 14 days of the laboratory test);
• ✓. Platelet count \>=75 \* 10\^9/L (without prior platelet transfusion within 7 days before the laboratory test) in participants in whom less than (\<) 50 percent (%) of bone marrow nucleated cells are plasma cells; platelet count \>=50 \* 10\^9/L (without prior platelet transfusion within 7 days before the laboratory test) in participants in whom \>=50% of bone marrow nucleated cells are plasma cells;
• ✓. Lymphocyte count \>=0.3 \* 10\^9/L;
• ✓. Aspartate aminotransferase (AST) less than or equal to (\<=)3 \* upper limit of normal (ULN);
• ✓. Alanine aminotransferase (ALT) \<=3 \* ULN;
• ✓. Total bilirubin \<=2.0 \* ULN; except in participants with congenital bilirubinemia, such as Gilbert syndrome (in which case direct bilirubin \<=1.5 \* ULN is required);
• ✓. Estimated glomerular filtration rate \>=40 milliliter per minute (mL/min) per 1.73 meter square (m\^2) (to be calculated using the Modification of Diet in Renal Disease \[MDRD\] formula)