A Study of Teclistamab With Other Anticancer Therapies in Participants With Multiple Myeloma

Inclusion Criteria: * Have documented initial diagnosis of multiple myeloma according to international myeloma working group (IMWG) diagnostic criteria * Meet treatment regimen-specific requirements as follows: Treatment Regimen A (teclistamab \[tec\]-daratumumab \[dara\]-pomalidomide \[pom\]) only: Participant has relapsed or refractory multiple myeloma and has received 1 to 3 prior lines of therapy, including exposure to a proteasome inhibitor (PI) and lenalidomide; Treatment Regimen B (tec-dara-lenalidomide \[len\]-bortezomib \[bor\]) only: Participant has newly diagnosed or relapsed/refractory multiple myeloma and is naive to treatment with lenalidomide; Treatment Regimen C (tec-nirogacestat \[niro\]) only: Participant has relapsed or refractory multiple myeloma and has 1) received 3 or more prior lines of therapy or 2) is double refractory to a PI and an immunomodulatory drug (IMiD) and triple exposed to a PI, an IMiD, and an anti-cluster of differentiation (CD)38 monoclonal antibody (mAb); Treatment Regimen D (tec-len) only: Participant has multiple myeloma and has received greater than or equal to (\>=) 2 prior lines of therapy, including exposure to a PI, an IMiD, and an anti-CD38 mAb; Treatment Regimen E (tec-dara-len) only: Participant has newly diagnosed multiple myeloma or if previously treated has received 1 to 3 prior lines of therapy, including exposure to a PI and an IMiD; Treatment Regimen F (tec-dara-len-bor) only: Participant has newly diagnosed multiple m…