Talquetamab

G protein-coupled receptor class C group 5 member D (GPRC5D) is an orphan G protein-coupled receptor predominantly expressed in cells with a plasma-cell phenotype, including the malignant plasma cells in multiple myeloma (MM). This transmembrane receptor protein is often aberrantly expressed in MM cells. In contrast, in normal tissues, it is primarily expressed in epithelial cells that produce hard keratin in the skin and tongue.

Talquetamab is a bispecific T-cell-engaging antibody that binds to the CD3 receptor expressed on the surface of T-cells and GPRC5D expressed on the surface of MM cells. It works to recruit CD3-expressing T cells to GPRC5D-expressing MM cells to induce T-cell–mediated cytotoxicity, prevent tumour growth, and promote tumour regression. When activated, T cells cause the release of proinflammatory cytokines, promoting the lysis of MM cells.