CRS0393

CRS0393 is a benzothiazole amide small molecule antibacterial agent in preclinical development for the treatment of pulmonary nontuberculous mycobacterial (NTM) disease, including infections caused by *Mycobacterium abscessus*. It acts by selectively inhibiting the essential mycobacterial membrane protein MmpL3, which is required for cell wall biosynthesis. Preclinical studies have demonstrated that CRS0393 has excellent *in vitro* activity against NTM, with minimum inhibitory concentrations (MICs) as low as ≤0.03-0.5 μg/mL against clinical isolates of *M. abscessus* from cystic fibrosis patients[6][1]. The compound shows good oral bioavailability and achieves high concentrations in lung tissue and epithelial lining fluid after intratracheal or oral administration in animal models[1][6]. In macrophage infection models, CRS0393 reduces intracellular *M. abscessus* burden in a concentration-dependent manner[1]. The drug is being developed by Crestone for both inhaled and oral therapy routes to address difficult-to-treat pulmonary NTM infections[2][5].