Here, we describe two efficacy studies in which inhaled CPZEN-45 was tested for its ability to treat TB in a guinea pig model.To our knowledge, this is the first report on the effect of CPZEN-45, delivered by any route, to treat TB in an animal model of infection.The results indicate the ability of inhaled CPZEN-45 to affect Mtb burden and lung pathol.CPZEN-45 was evaluated as monotherapy in these studies because the goal was to simply assess efficacy of drug.However, for future clin. use CPZEN-45 would most likely be added to the standard of care or used to replace a current component of multidrug regimens.While observing an effect of drug alone is critical for drug development progression, it is understood that any drug used in TB treatment will be employed in a new multiple drug regimen or to supplement or replace a component of an existing regimen.Future studies will evaluate the additive or synergistic effects of inhaled CPZEN-45 with other drugs in the treatment regimen.Taken together, the results presented here are significant in being the first to demonstrate the potential for the new drug CPZEN-45 to be used as a component of TB treatment by delivering it to the lungs by aerosol, as an approach to overcome its poor oral bioavailability.