MM3122

MM3122 is a potent, selective small-molecule inhibitor of the type II transmembrane serine protease TMPRSS2. It was developed as an antiviral agent targeting host cell entry mechanisms exploited by viruses such as SARS-CoV-2 (the virus responsible for COVID-19), other coronaviruses (including SARS-CoV and MERS-CoV), and influenza viruses. By inhibiting TMPRSS2, which is essential for viral spike protein activation and subsequent membrane fusion, MM3122 blocks viral entry into human cells. The compound also inhibits related serine proteases such as matriptase and hepsin with subnanomolar potency. In preclinical studies, MM3122 demonstrated superior antiviral activity compared to remdesivir, camostat, and nafamostat without cytotoxicity in cell models. In mouse models of COVID-19 infection, it provided significant protection against weight loss and lung pathology when administered prophylactically or therapeutically. Developed at Washington University School of Medicine in St. Louis by Dr. Daniel Janetka’s group, MM3122 represents a promising lead candidate for the treatment and prevention of COVID-19 and potentially other respiratory viral infections[3][5][6][8].