Mertansine

Mertansine, also called DM1 (and in some of its forms emtansine), is a thiol-containing maytansinoid that for therapeutic purposes is attached to a monoclonal antibody through reaction of the thiol group with a linker structure to create an antibody-drug conjugate (ADC). Mertansine, also called DM1 (and in some of its forms emtansine), is a thiol-containing maytansinoid that for therapeutic purposes is attached to a monoclonal antibody through reaction of the thiol group with a linker structure to create an antibody-drug conjugate (ADC). ADCs with this design include trastuzumab emtansine, lorvotuzumab mertansine, and cantuzumab mertansine. Some are still experimental; others are in regular clinical use. Mertansine is a tubulin inhibitor, meaning that it inhibits the assembly of microtubules by binding to tubulin (at the rhizoxin binding site). The monoclonal antibody binds specifically to a structure (usually a protein) occurring in a tumour, thus directing mertansine into this tumour. This concept is called targeted therapy. The following (experimental) drugs are antibody-drug conjugates (ADC) combining monoclonal antibodies with mertansine as the cytotoxic component. Mertansine is linked via 4-mercaptovaleric acid.