TTX-564 is a multi-functional molecule that targets leukemic cells in addition to non-cancerous myeloid-derived suppressor cells (MDSCs) to restore a robust anti-tumor immune response. By design, TTX-564 spares healthy myeloid cells thus allowing safe and convenient self-administration by patients at home.
In cancer patients, the generation of new blood cells is biased toward immune suppressive MDSCs which block a robust anti-tumor T cell response. Additionally, MDSCs are a key reason why T-cell activating therapies like PD1 inhibitors fail to durably treat disease.
TTX-564 is bispecific CD3/CD33 T cell engager whose bivalent design allows it to selectively bind cells that express clustered CD33. By doing so, TTX-564 potently eliminates leukemic blasts and immune suppressive MDCSs, but spares healthy myeloid cells such as monocytes and neutrophils. By eliminating MDSCs, TTX-564 induces T cell activation and expansion in cancer patients without causing cytokine release syndrome. TTX-564 has demonstrated monotherapy activity in solid tumor and hematologic cancer patients with an excellent clinical safety profile alone or in combination with checkpoint inhibition. These early signals of clinical activity support our goal to bring new treatment options to cancer patients underserved by immunotherapy.