MT-0169

MT-0169 is a next-generation engineered toxin body (ETB) designed as a dimeric recombinant fusion protein that targets CD38, a cell surface antigen highly expressed on multiple myeloma and some non-Hodgkin lymphoma cells. It consists of a human single-chain variable antibody fragment specific for CD38 fused to an enzymatically active, de-immunized Shiga-like toxin A subunit (SLTA). Upon binding to CD38, MT-0169 is internalized by the target cell, where the SLTA payload irreversibly inhibits ribosomal function by removing an adenine base from the 28S rRNA subunit. This leads to inhibition of protein synthesis and activation of caspase-mediated apoptosis in malignant cells. Preclinical studies have shown potent activity against multiple myeloma cells—including those refractory to other anti-CD38 therapies—with minimal toxicity toward nonmalignant hematopoietic cells. The drug was developed primarily for relapsed or refractory multiple myeloma and has also been investigated in non-Hodgkin lymphoma[2][3][6][8].