CTX-100

CTX-100 (formerly ETX-100) is an inhaled small molecule drug candidate developed for the treatment of chronic obstructive pulmonary disease (COPD). It acts as a potent inhibitor of elastin breakdown, specifically targeting **neutrophil elastase** (NE), a protease that plays a central role in the degradation of lung parenchyma and the progression of emphysema. Originally developed by EpiTherapeutix and acquired by Celtaxsys in 2008, CTX-100 was formulated as an inhalation solution to provide targeted delivery to the lungs while minimizing systemic exposure and associated side effects. A Phase 1 clinical trial (NCT00993707) was conducted to evaluate its safety and biochemical activity, measured by the reduction of elastin degradation markers in patients with smoking-related COPD. However, clinical development appears to have been halted following the completion of early-stage studies, as the developer shifted focus to other pipeline candidates like acebilustat.