An international consortium led by IRB Barcelona and the company Merus has discovered MCLA-158, an antibody that targets cancer stem cells in solid tumors and prevents metastasis in experimental models.
The MCLA-158 antibody, commercially known as Petosemtamab, is a bispecific antibody that recognizes two distinct proteins on the surface of cancer stem cells, namely EGFR and LGR5. EGFR activity promotes uncontrolled cell growth, while LGR5 marks the surface of cancer stem cells, which are responsible for tumor expansion.
The mechanism of action of Petosemtamab involves the degradation of the EGFR protein in cancer stem cells bearing the LGR5 marker, thus blocking the growth and survival pathways in cancer-initiating and cancer-spreading cells, blocking the development of metastases and slowing the growth of primary tumors. This antibody, however, does not interfere with the functioning of the body’s healthy stem cells, which are essential for the proper functioning of tissues. A clinical trial is underway to test it in humans.