A Study to Compare the Efficacy and Safety of BMS-986393 Versus Standard Regimens in Adult Participants With Relapsed or Refractory and Lenalidomide-exposed Multiple Myeloma (QUINTESSENTIAL-2)

Inclusion Criteria * Participants must have relapsed or refractory multiple myeloma (RRMM). * Participants must have received at least 1 but no greater than 3 prior multiple myeloma (MM) regimens which may include a proteasome inhibitor (PI), an immunomodulatory drug (IMiD), and an anti-CD38 monoclonal antibody and have prior exposure to lenalidomide. * Participants must have a documented diagnosis of MM as per International Myeloma Working Group Criteria. * Participants must have measurable disease during screening. * Participants must have adequate organ function. * Participants must have an Eastern Cooperative Oncology group performance status 0 or 1. Exclusion Criteria * Participants must not have known active or history of central nervous system (CNS) involvement of Multiple Myeloma (MM). * Participants must not have solitary plasmacytomas or non-secretory myeloma without other evidence of measurable disease. * Participants must not need urgent treatment due to rapidly progressing MM. * Other protocol-defined Inclusion/Exclusion criteria apply.