DOP 126

DOP 126 is a novel small-molecule ligand of the delta opioid receptor (DOR), designed as a derivative of the selective DOR antagonist naltrindole. Developed through rational design by researchers at the University of Medicine and Dentistry of New Jersey (UMDNJ), DOP 126 was identified as a potential therapeutic agent for multiple myeloma. In preclinical studies, DOP 126 demonstrated high affinity for the naltrindole binding site on human U266 multiple myeloma cells and significantly inhibited their proliferation in vitro. Its mechanism of action involves binding to the delta opioid receptor or a related non-opioid target that mediates anti-proliferative and immunosuppressive effects in plasma cell neoplasms. The compound was modeled from naltrindole to improve upon its efficacy in inhibiting myeloma cell growth.