Achaogen is developing novel antibiotics that inhibit outer membrane biosynthesis via a previously unexploited target, known as LpxC. These first-in-class agents have a novel mechanism of action, and are potent against a broad spectrum of MDR Gram-negative bacteria with no pre-existing clinical resistance. Our compounds have strong antibacterial activity (MIC <1 μg/ml) against MDR P. aeruginosa and MDR E. coli, and are active against weaponizable pathogens such as Y. pestis and other important clinical Gram-negative pathogens.