Bispecific antibodies (or T cell engagers) are another targeted approach to specifically kill myeloma cells. They work by binding to antigens on a T cell and a myeloma cell and therefore bring the two together, initiating an immune response. There are several bispecific antibodies currently available through clinical trials for relapsed/refractory myeloma.
Elranatamab and teclistamab are both in late phase trials and work by binding to BCMA on myeloma cells and CD3 on T cells. Cevostamab and REGN5458 work via the same mechanism but are in early phase trials. All T cell engagers can cause side effects. These include cytopenia, infections, and neurological side effects (such as delirium and confusion). Sometimes patients can experience cytokine release syndrome (CRS) leading to flu like symptoms.