Peking University, May 18, 2026: Chronic itch is often described as an "invisible torment." It can persist for weeks or months, severely affecting sleep, mental health, and quality of life. In patients with cholestatic liver disease, chronic itch remains a major clinical challenge, and current treatments often provide limited relief. A team led by PKU's Professor Lei Xiaoguang, together with Hepai-Tech Biopharma Technology and collaborators from the University of Science and Technology of China (USTC) and the Hefei Comprehensive National Science Center, has developed HEP-50768, a potent and selective small-molecule inverse agonist targeting the itch receptor MRGPRX4. The study was published in Nature Chemical Biology.