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 arlocabtagene
autoleucel (BMS-986393) in combinations with alnuctamab, mezigdomide, iberdomide, and
elranatamab 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:

- Prior treatment with alnuctamab (Arm A), mezigdomide (Arm B), iberdomide (Arm C),
elranatamab (Arm D) or BCMA-targeting therapy (Part 2 Arms A and D).

- Prior treatment with GPRC5D-targeting therapies.

Note: Other protocol-defined inclusion/exclusion criteria apply