Pretomanid (PA-824) is an experimental anti-tuberculosis drug. Pretomanid is a bicyclic nitroimidazole-like molecule with a very complex mechanism of action. It is active against both replicating and hypoxic, non-replicating Mycobacterium tuberculosis. As a potential TB therapy, it has many attractive characteristics - most notably its novel mechanism of action, its activity in vitro against all tested drug-resistant clinical isolates, and its activity as both a potent bactericidal and a sterilizing agent in mice. In addition, the compound shows no evidence of mutagenicity in a standard battery of genotoxicity studies, no significant cytochrome P450 interactions, and no significant activity against a broad range of Gram-positive and Gram-negative bacteria. This compound has been developed by TB Alliance and is a potential cornerstone of future TB and drug-resistant TB treatment regimens. It is currently undergoing Phase III clinical trials.