UMN-120

UMN-120 is an orally available next-generation rifamycin analog being developed as a novel antibiotic for drug-resistant mycobacterial lung infections, particularly Mycobacterium abscessus pulmonary disease. It is a C25-substituted rifamycin designed to retain the class’s validated mechanism of action—binding to and inhibiting bacterial DNA-dependent RNA polymerase—while improving potency, pharmacokinetics, and resistance evasion compared with existing rifamycins. In preclinical models, UMN-120 demonstrated very low minimum inhibitory concentrations against M. abscessus and Mycobacterium tuberculosis, high oral bioavailability, favorable AUC/MIC and serum-shift–corrected PK/PD indices, and potent bactericidal activity in mouse models of M. abscessus lung infection, where it reduced lung bacterial burden below the limit of detection and outperformed a standard multi-drug regimen.[1][3][5][7]