Elranatamab is a bispecific antibody approved by the FDA in August 2023 that offers a new treatment option for patients with multiple myeloma. Similar to teclistamab (Tecvayli), elranatamab works by targeting a protein called B-cell maturation antigen (BCMA) found on the surface of myeloma cells. This targeted approach helps recruit the body's own immune system to attack and destroy these cancer cells.

Elranatamab is intended for adults with multiple myeloma that has either:

• Relapsed after receiving at least four prior lines of therapy, including a proteasome inhibitor (like bortezomib or carfilzomib), an immunomodulatory agent (like lenalidomide or pomalidomide), and an anti-CD38 monoclonal antibody.
• Not responded well to initial treatment (refractory).

Elranatamab is administered subcutaneously (via injection). The initial treatment involves a specific dosing schedule with "step-up" priming doses, followed by regular bi-weekly infusions. The exact duration of treatment depends on individual patient tolerance and response.

The approval was based on the results of the Phase 2 trial (MagnetisMM-3), where elranatamab produced an overall response rate of 58%, with 26% of patients achieving a complete remission. These results suggest that elranatamab can be effective in patients who haven't responded well to other treatments. Of note, 33% of patients who received a previous BCMA-directed therapy responded to elranatamab.

Some of the most common side effects reported in elranatamab’s clinical trials include: CRS in up to 58% of patients, with most cases being manageable; low blood cell counts (neutropenia) in around 48% of patients, with an increased risk of infections; and neurological toxicities in 59% of patients, which can include confusion, dizziness, and difficulty walking or speaking.