BTZ-043 is a small-molecule antitubercular agent in the benzothiazinone (BTZ) class. It exerts potent anti-Mycobacterium tuberculosis activity by irreversibly inhibiting the flavoenzyme DprE1, which is essential for the synthesis of cell-wall arabinan components, leading to bacterial death. BTZ-043 displays nanomolar MICs against both drug-sensitive and multidrug- or extensively drug-resistant M. tuberculosis strains and has demonstrated superior efficacy compared to isoniazid in mouse models, including potent activity in pulmonary lesions and granulomas. Preclinical toxicology studies have shown a favorable safety profile, including low toxicity (well tolerated at high doses in rodents and minipigs), absence of genotoxicity or mutagenicity, minimal cytochrome P450 or hERG interactions, and irreversible covalent binding to its target.