A Phase 1, Multicenter, Open-label Study to Evaluate the Safety and Preliminary Efficacy of BMS-986393 in Novel Combinations in Participants with Relapsed and/or Refractory Multiple Myeloma and Determine the Recommended Dose for Each Add-on Investigational Component (Phase I GPRC5D Combo)

The purpose of this study is to establish a safe and tolerable dose of BMS-986393 in
combinations with alnuctamab, mezigdomide, and iberdomide in participants with relapsed
and/or refractory multiple myeloma (RRMM).

Inclusion Criteria:

- History of relapsed and/or refractory multiple myeloma (RRMM) treated with at least
3 (Part 1 and Part 2) or at least 1 but not greater than 3 prior anti-myeloma
treatment regimens (Part 2)

- Measurable multiple myeloma (MM)

- Eastern Cooperative Oncology Group performance status of 0-1

Exclusion Criteria:

- Condition that confounds the ability to interpret data from the study

- Known active or history of central nervous system (CNS) involvement of MM

Note: Other protocol-defined inclusion/exclusion criteria apply