Cilta-cel (JNJ-68284528/LCAR-B38M chimeric antigen receptor T-cells [CAR-T]) is an autologous CAR-T therapy that targets B-cell maturation antigen (BCMA), a molecule expressed on the surface of mature B lymphocytes and malignant plasma cells. There will be no treatment administered during the study and the data obtained from this study will help to assess whether there will be long-term cilta-cel-related toxicities. The study will consist of 2 phases: within the first 5 years after receiving the last dose of cilta-cel and Year 6 to 15 years after last dose of cilta-cel. Safety evaluations will include a review of adverse events, laboratory test results, and physical examination findings (including neurological examination). The duration of the study is up to 15 years after last dose of cilta-cel and participants will be followed at least once per year.

Cilta-cel (JNJ-68284528/LCAR-B38M chimeric antigen receptor T-cells \[CAR-T\]) is an autologous CAR-T therapy that targets B-cell maturation antigen (BCMA), a molecule expressed on the surface of mature B lymphocytes and malignant plasma cells. There will be no treatment administered during the study and the data obtained from this study will help to assess whether there will be long-term cilta-cel-related toxicities. The study will consist of 2 phases: within the first 5 years after receiving the last dose of cilta-cel and Year 6 to 15 years after last dose of cilta-cel. Safety evaluations will include a review of adverse events, laboratory test results, and physical examination findings (including neurological examination). The duration of the study is up to 15 years after last dose of cilta-cel and participants will be followed at least once per year.