ML-800

ML-800 is a melanocortin 1 receptor (MC1R)-targeted optical imaging probe developed for the detection and molecular imaging of melanoma. It consists of a high-affinity peptidomimetic ligand specific for MC1R conjugated to an infrared dye. MC1R is a G protein-coupled receptor that is significantly overexpressed in the majority of human melanoma metastases while maintaining low expression in normal skin and other vital organs, providing a high signal-to-noise ratio for imaging. In preclinical studies, ML-800 demonstrated a high binding affinity (Ki of 0.4 nM) and specific accumulation in MC1R-expressing tumors in mouse models. Developed by researchers at the Moffitt Cancer Center and the University of Arizona, ML-800 serves as a prototype for the targeted delivery of imaging contrast or therapeutic agents to melanoma metastases.