# Elranatamab for Treatment of Multiple Myeloma With Central Nervous Involvement Refractory to Other Interventions

## TL;DR

Elranatamab successfully treated multiple myeloma with central nervous system involvement, leading to full recovery and sustained remission.

## Contribution

Demonstrates the efficacy of sequential bispecific antibody and CAR-T therapy in a rare and severe myeloma case.

## Key findings

- Elranatamab achieved complete serological and CNS response in a refractory patient.
- The patient regained full independence and remained in sustained MRD negativity after CAR-T therapy.
- Sequential immunotherapy offers new hope for CNS multiple myeloma.

## Abstract

Plasma cell leukemia and central nervous system involvement are two poor prognostic factors in myeloma, and such patients are often excluded from clinical trials.

A 59‐year‐old patient with primary plasma cell leukemia developed leptomeningeal CNS disease following autologous transplant. Intrathecal chemotherapy and selinexor, pomalidomide, and dexamethasone failed to clear cerebrospinal fluid plasma cells.

Elranatamab achieved complete serological and CNS response. The patient recovered from bedbound status to full independence and proceeded to receive CAR‐T therapy. At 8 months post CAR‐T, he remains in sustained MRD negativity.

Sequential bispecific antibody and CAR‐T therapy demonstrates exceptional efficacy in CNS multiple myeloma, offering new hope for this historically terminal condition and supporting the systematic study of novel immunotherapies in high‐risk myeloma populations.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.